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Sample records for adirondack mountain lakes

  1. Response of fish assemblages to declining acidic deposition in Adirondack Mountain lakes, 1984-2012

    NASA Astrophysics Data System (ADS)

    Baldigo, B. P.; Roy, K. M.; Driscoll, C. T.

    2016-12-01

    Adverse effects of acidic deposition on the chemistry and fish communities were evident in Adirondack Mountain lakes during the 1980s and 1990s. Fish assemblages and water chemistry in 43 Adirondack Long-Term Monitoring (ALTM) lakes were sampled by the Adirondack Lakes Survey Corporation and the New York State Department of Environmental Conservation during three periods (1984-87, 1994-2005, and 2008-12) to document regional impacts and potential biological recovery associated with the 1990 amendments to the 1963 Clean Air Act (CAA). We assessed standardized data from 43 lakes sampled during the three periods to quantify the response of fish-community richness, total fish abundance, and brook trout (Salvelinus fontinalis) abundance to declining acidity that resulted from changes in U.S. air-quality management between 1984 and 2012. During the 28-year period, mean acid neutralizing capacity (ANC) increased significantly from 3 to 30 μeq/L and mean inorganic monomeric Al concentrations decreased significantly from 2.22 to 0.66 μmol/L, yet mean species richness, all species or total catch per net night (CPNN), and brook trout CPNN did not change significantly in the 43 lakes. Regression analyses indicate that fishery metrics were not directly related to the degree of chemical recovery and that brook trout CPNN may actually have declined with increasing ANC. While the richness of fish communities increased with increasing ANC as anticipated in several Adirondack lakes, observed improvements in water quality associated with the CAA have generally failed to produce detectable shifts in fish assemblages within a large number of ALTM lakes. Additional time may simply be needed for biological recovery to progress, or else more proactive efforts may be necessary to restore natural fish assemblages in Adirondack lakes in which water chemistry is steadily recovering from acidification.

  2. Response of fish assemblages to declining acidic deposition in Adirondack Mountain lakes, 1984–2012

    USGS Publications Warehouse

    Baldigo, Barry P.; Roy, Karen; Driscoll, Charles T.

    2016-01-01

    Adverse effects of acidic deposition on the chemistry and fish communities were evident in Adirondack Mountain lakes during the 1980s and 1990s. Fish assemblages and water chemistry in 43 Adirondack Long-Term Monitoring (ALTM) lakes were sampled by the Adirondack Lakes Survey Corporation and the New York State Department of Environmental Conservation during three periods (1984–87, 1994–2005, and 2008–12) to document regional impacts and potential biological recovery associated with the 1990 amendments to the 1963 Clean Air Act (CAA). We assessed standardized data from 43 lakes sampled during the three periods to quantify the response of fish-community richness, total fish abundance, and brook trout (Salvelinus fontinalis) abundance to declining acidity that resulted from changes in U.S. air-quality management between 1984 and 2012. During the 28-year period, mean acid neutralizing capacity (ANC) increased significantly from 3 to 30 μeq/L and mean inorganic monomeric Al concentrations decreased significantly from 2.22 to 0.66 μmol/L, yet mean species richness, all species or total catch per net night (CPNN), and brook trout CPNN did not change significantly in the 43 lakes. Regression analyses indicate that fishery metrics were not directly related to the degree of chemical recovery and that brook trout CPNN may actually have declined with increasing ANC. While the richness of fish communities increased with increasing ANC as anticipated in several Adirondack lakes, observed improvements in water quality associated with the CAA have generally failed to produce detectable shifts in fish assemblages within a large number of ALTM lakes. Additional time may simply be needed for biological recovery to progress, or else more proactive efforts may be necessary to restore natural fish assemblages in Adirondack lakes in which water chemistry is steadily recovering from acidification.

  3. Acid precipitation effects on algal productivity and biomass in Adirondack Mountain lakes

    SciTech Connect

    Hendrey, G.R.

    1982-12-01

    Relationships between phytoplankton communities and lake acidity in three Adirondack Mountain lakes were studied at Woods Lake (pH ca. 4.9), Sagamore Lake (pH ca. 5.5), and Panther Lake (pH ca. 7.0). Species numbers decrease with increasing acidity. Patterns of increasing biomass and productivity in Woods Lake may be atypical of similar oligotrophic lakes in that they develop rather slowly to maxima six weeks after ice-out, instead of occurring very close to ice-out. Contributions of netplankton, nannoplankton and ultraplankton to productivity per m/sup 2/ show that the smaller plankton are relatively more important in the more acid lakes. This pattern could be determined by nutrient availability (lake acidification is suspected of leading to decreased availability of phosphorus). This was consistent with a hypothesis that microbial heterotrophic activity is reduced with increasing acidity, but the smaller phytoplankton may be more leaky at low pH. 11 references, 2 tables.

  4. Geologic controls on the sources of water to Lake George, Southeastern Adirondack Mountains of New York

    SciTech Connect

    Shuster, E.L.; LaFleur, R.G.; McCaffrey, R. . Dept. of Earth and Environmental Sciences); Boylen, C.W. . Rensselaer Fresh Water Inst.)

    1993-03-01

    Lake George is a long, deep, fault-bounded lake in the Adirondack Mountains, with relatively undeformed Paleozoic sediments in its valley floor and fractured high-grade meta-igneous and meta-sedimentary Proterozoic rocks in the drainage basins's upland. Overlying these rocks is a thin mantle of glacial deposits, consisting of sandy tills, kamic sands and glacio-lacustrine clays. Stratified ice-contact deposits and glacio-lacustrine deposits are generally restricted to the basins's lower elevations. The configuration of fractured bedrock and glacial overburden deposits of varying hydraulic conductivities suggests a variety of potential hydrogeologic flow routes, which can be generally categorized as reflect near-surface and deep groundwater flow systems. A hydrologic survey of the lake suggests that groundwater contributes approximately 20% to Lake George's annual hydrologic budget, with precipitation directly onto the lake's surface and tributary streamflow comprising the remaining 25% and 55%, respectively. Separating streamflow responses to precipitation by formal inversion into quick-, intermediate-, and slow-recession curves (originating from soils, unconsolidated surficial deposits, and fractured bedrock, respectively) suggests that as much as 40 to 50% of the tributary streamflow during the summer of 1988 originated from the slowest return route, a similar percentage has followed the intermediate route, and less than 10% of the streamflow originated as soil water ( runoff''). The flow-partitioning calculations typically suggest decay constants for these exponential recession curves on the order of 1, 10, and 100 days for the quick-, intermediate-, and slow-flow components to tributary streamflow, respectively.

  5. The reflectance and fluorescence properties of Adirondack mountain region lakes applied to the remote sensing of lake chemistry

    SciTech Connect

    Vertucci, F.A.

    1988-01-01

    This study defines the feasibility of the remote monitoring of lake chemistry in the Adirondack Region of New York. The purpose of this thesis is to determine the relationship between the optical properties of lakes and their chemical constituents. The work is intended to derive useful relationships between lake chemistry and lake spectral properties so that lake chemistry can be estimated by remote means. Chemical constituents associated with lake acidification are of particular interest. Constituents of the water column which are known to directly affect lake optical properties (plant pigments, dissolved organic carbon (DOC) and turbidity) correlated well with field reflectance measurements and allowed for a consistent prediction of the concentrations of these constituents using reflectance measurements. However, parameters associated with acidification (pH, alkalinity and aluminum concentrations) correlated poorly with reflectance measurements and no models for prediction of these constituents were possible. A relationship does exist between DOC and fluorescence intensity and also between lake pH, aluminum and DOC concentrations and spectral fluorescence and intensity. In the Adirondack Region, water column constituents which directly affect lake optical properties may e remotely estimated with reflectance measures while constituents correlated with DOC composition may be estimated by laser fluorsensing, including pH and aluminum.

  6. Paleoecological investigation of recent lake acidification in the Adirondack Mountains, NY

    SciTech Connect

    Charles, D.F.; Binford, M.W.; Furlong, E.T.; Hites, R.A.; Mitchell, M.J.

    1990-01-01

    Paleoecological analysis of the sediment record of 12 Adirondack lakes reveals that the 8 clearwater lakes with current pH<5.5 and alkalinity <10 microeq/l have acidified recently. The onset of the acidification occurred between 1920 and 1970. Loss of alkalinity, based on quantitative analysis of diatom assemblages, ranged from 2 to 35 microeq/l. The acidification trends are substantiated by several lines of evidence including stratigraphies of diatom, chrysophyte, chironomid, and cladoceran remains, Ca:Ti and Mn:Ti ratios, sequentially extracted forms of Al, and historical fish data. Acidification trends appear to be continuing in some lakes, despite reductions in atmospheric sulfur loading that began in the early 1970s. The primary cause of the acidification trend is clearly increased atmospheric deposition of strong acids derived from the combustion of fossil fuels. Natural processes and watershed disturbances cannot account for the changes in water chemistry that have occurred, but they may play a role. Sediment core profiles of Pb, Cu, V, Zn, S, polycyclic aromatic hydrocarbons, magnetic particles, and coal and oil soot provide a clear record of increased atmospheric input of materials associated with the combustion of fossil fuels beginning in the late 1800s and early 1900s.

  7. Hydrologic analysis of two headwater lake basins of differing lake pH in the west-central Adirondack Mountains of New York

    USGS Publications Warehouse

    Murdoch, Peter S.; Peters, N.E.; Newton, R.M.

    1987-01-01

    Hydrologic analysis of two headwater lake basins in the Adirondack Mountains, New York, during 1980-81 indicates that the degree of neutralization of acid precipitation is controlled by the groundwater contribution to the lake. According to flow-duration analyses, daily mean outflow/unit area from the neutral lake (Panther Lake, pH 5-7) was more sustained and contained a higher percentage of groundwater than that of the acidic lake (Woods Lake, pH 4-5). Outflow recession rates and maximum base-flow rates, derived from individual recession curves, were 3.9 times and 1.5 times greater, respectively, in the neutral-lake basin than in the acidic-lake basin. Groundwater contribution to lake outflow was also calculated from a lake-water budget; the groundwater contribution to the neutral lake was about 10 times greater than that to the acidic lake. Thick sandy till forms the groundwater reservoir and the major recharge area in both basins but covers 8.5 times more area in the neutral-lake basin than in the acidic-lake basin. More groundwater storage within the neutral basin provides longer contact time with neutralizing minerals and more groundwater discharge. As a result, the neutral lake has relatively high pH and alkalinity, and more net cation transport. (USGS)

  8. Chemical characteristics of Adirondack lakes

    SciTech Connect

    Driscoll, C.T.; Newton, R.M.

    1985-11-01

    This paper discussed the role of atmospheric deposition of mineral acids in the acidification of low-ionic-strength (dilute) surface waters in remote regions. Surface water acidification has been attributed to the atmospheric deposition of sulfuric acid, sulfur dioxide, and nitric acid, the oxidation of organic nitrogen from the soil, the production of soluble organic acids through the decay of dead plants and animals in soil, the oxidation of naturally occurring sulfide minerals, and the changes in land use. The research reported here was conducted as part of the Regionalized Integrated Lake-Watershed Acidification Study (RILWAS). The intent was to evaluate the general chemical characteristics of lakes in the Adirondack region of New York and to access the mechanisms that regulate the acid-base chemistry of these waters. 36 references, 5 figures, 3 tables.

  9. Episodic acidification of Adirondack lakes during snowmelt

    SciTech Connect

    Schaefer, D.A.; Driscoll, C.T.; Van Dreason, R.; Yatsko, C.P.

    1990-07-01

    Maximum values of acid neutralizing capacity (ANC) in Adirondack, New York lake outlets generally occur during summer and autumn. During spring snowmelt, transport of acidic water through acid-sensitive watersheds causes depression of upper lake water ANC. In some systems lake outlet ANC reaches negative values. The authors examined outlet water chemistry from II Adirondack lakes during 1986 and 1987 snowmelts. In these lakes, SO concentrations were diluted during snowmelt and did not depress ANC. For lakes with high baseline ANC values, springtime ANC depressions were primarily accompanied by basic cation dilution. For lakes with low baseline ANC, No increases dominated ANC depressions. Lakes with intermediate baseline ANC were affected by both processes and exhibited larger ANC depressions. Ammonium dilution only affected wetland systems. A model predicting a linear relationship between outlet water ANC minima and autumn ANC was inappropriate. To assess watershed response to episodic acidification, hydrologic flow paths must be considered. (Copyright (c) 1990 by the American Geophysical Union.)

  10. USE OF A LUMPED MODEL (MAGIC) TO BOUND THE ESTIMATION OF POTENTIAL FUTURE EFFECTS OF SULFUR AND NITROGEN DEPOSITION ON LAKE CHEMISTRY IN THE ADIRONDACK MOUNTAINS

    EPA Science Inventory

    Leaching of atmospherically deposited nitrogen from forested watersheds can acidify lakes and streams. Using a modified version of the Model of Acidification of Groundwater in Catchments, we made computer simulations of such effects for 36 lake catchments in the Adirondack Mount...

  11. Mercury contribution to an adirondack lake

    NASA Astrophysics Data System (ADS)

    Scrudato, R. J.; Long, D.; Weinbloom, Robert

    1987-10-01

    Elevated copper, lead, and zinc concentrations in the upper 10 to 20 cm of sediment sampled from Cranberry Lake, a large Adirondack lake, are attributed to atmospheric contributions. Pb-210 and pollen core data, however, suggest Cranberry Lake also received mercury discharges during the turn of the century when the area was the center of extensive lumbering and related activities. Elevated mercury concentrations in Cranberry Lake smallmouth bass derived from remobilization from mercury-contaminated bottom sediments which increased the bioavailability to Cranberry Lake organisms. Mercury remobilization and accumulation by fish are promoted by fluctuating pH values resulting from acid precipilation.

  12. Mercury contribution to an Adirondack lake

    SciTech Connect

    Scrudato, R.J. ); Long, D. ); Weinbloom, R. )

    1987-01-01

    Elevated copper, lead, and zinc concentrations in the upper 10 to 20 cm of sediment sampled from Cranberry Lake, a large Adirondack lake, are attributed to atmospheric contributions. Pb-210 and pollen core data, however, suggest Cranberry Lake also received mercury discharges during the turn of the century when the area was the center of extensive lumbering and related activities. Elevated mercury concentrations in Cranberry Lake smallmouth bass derived from remobilization from mercury-contaminated bottom sediments which increased the bioavailability to Cranberry Lake organisms. Mercury remobilization and accumulation by fish are promoted by fluctuating pH values resulting from acid precipitation.

  13. Chloride cycling in two forested lake watersheds in the west-central Adirondack Mountains, New York, U.S.A.

    USGS Publications Warehouse

    Peters, N.E.

    1991-01-01

    The chemistry of precipitation, throughfall, soil water, ground water, and surface water was evaluated in two forested lake-watersheds over a 4-yr period to assess factors controlling C1- cycling. Results indicate that C1- cycling in these watersheds is more complex than the generally held view of the rapid transport of atmospherically derived C1- through the ecosystem. The annual throughfall Cl- flux for individual species in the northern hardwood forest was 2 to 5 times that of precipitation (56 eq ha-1), whereas the Na+ throughfall flux, in general, was similar to the precipitation flux. Concentrations of soil-water Cl- sampled from ceramic tension lysimeters at 20 cm below land surface generally exceeded the Na+ concentrations and averaged 31 ??eq L-1, the highest of any waters sampled in the watersheds, except throughfall under red spruce which averaged 34 ??eq L-1. Chloride was concentrated prior to storms and mobilized rapidly during storms as suggested by increases in streamwater Cl- concentrations with increasing flow. Major sources of Cl- in both watersheds are the forest floor and hornblende weathering in the soils and till. In the Panther Lake watershed, which contains mainly thick deposits of till( > 3 m), hornblende weathering results in a net Cl- flux 3 times greater than that in the Woods Lake watershed, which contains mainly thin deposits of till. The estimated accumulation rate of Cl- in the biomass of the two watersheds was comparable to the precipitation Cl- flux.The chemistry of precipitation, throughfall, soil water, ground water, and surface water was evaluated in two forested lake-watersheds over a 4-yr period to assess factors controlling Cl- cycling. Results indicate that Cl- cycling in these watersheds is more complex than the generally held view of the rapid transport of atmospherically derived Cl- through the excosystem. The annual throughfall Cl- flux for individual species in the northern hardwood forest was 2 to 5 times that of

  14. Hydrogeologic comparison of an acidic-lake basin with a neutral-lake basin in the West-Central Adirondack Mountains, New York

    USGS Publications Warehouse

    Peters, N.E.; Murdoch, Peter S.

    1985-01-01

    Two small headwater lake basins that receive similar amounts of acidic atmospheric deposition have significantly different lake outflow pH values; pH at Panther Lake (neutral) ranges from about 4.7 to 7; that at Woods Lake (acidic) ranges from about 4.3 to 5. A hydrologic analysis, which included monthly water budgets, hydrograph analysis, examination of flow duration and runoff recession curves, calculation of ground-water storage, and an analysis of lateral flow capacity of the soil, indicates that differences in lakewater pH can be attributed to differences in the ground-water contribution to the lakes. A larger percentage of the water discharged from the neutral lake is derived from ground water than that from the acidic lake. Ground water has a higher pH resulting from a sufficiently long residence time for neutralizing chemical reactions to occur with the till. The difference in ground-water contribution is attributed to a more extensive distribution of thick till (<3m) in the neutral-lake basin than in the acidic-lake basin; average thickness of till in the neutral-lake basin is 24m whereas that in the other is 2.3m. During the snowmelt period, as much as three months of accumulated precipitation may be released within two weeks causing the lateral flow capacity of the deeper mineral soil to be exceeded in the neutral-lake basin. This excess water moves over and through the shallow acidic soil horizons and causes the lakewater pH to decrease during snowmelt.Two small headwater lake basins that receive similar amounts of acidic atmospheric deposition have significantly different lake outflow pH values; pH at Panther Lake (neutral) ranges from about 4. 7 to 7; that at Woods Lake (acidic) ranges from about 4. 3 to 5. A hydrologic analysis, which included monthly water budgets, hydrograph analysis, examination of flow duration and runoff recession curves, calculation of ground-water storage, and an analysis of lateral flow capacity of the soil, indicates that

  15. Patterns of nutrient dynamics in Adirondack lakes recovering from acid deposition.

    PubMed

    Gerson, Jacqueline R; Driscoll, Charles T; Roy, Karen M

    2016-09-01

    With decreases in acid deposition, nitrogen : phosphorus (N:P) ratios in lakes are anticipated to decline, decreasing P limitation of phytoplankton and potentially changing current food web dynamics. This effect could be particularly pronounced in the Adirondack Mountains of New York State, a historic hotspot for effects of acid deposition. In this study, we evaluate spatial patterns of nutrient dynamics in Adirondack lakes and use these to infer potential future temporal trends. We calculated Mann-Kendall tau correlations among total phosphorus (TP), chlorophyll a, dissolved organic carbon (DOC), acid neutralizing capacity (ANC), and nitrate (NO3(-) ) concentrations in 52 Adirondack Long Term Monitoring (ALTM) program lakes using samples collected monthly during 2008-2012. We evaluated the hypothesis that decreased atmospheric N and S deposition will decrease P limitation in freshwater ecosystems historically impacted by acidification. We also compared these patterns among lake watershed characteristics (i.e., seepage or lacking a surface outlet, chain drainage, headwater drainage, thin glacial till, medium glacial till). We found that correlations (P < 0.05) were highly dependent upon the different hydrologic flowpaths of seepage vs. drainage lakes. Differentiations among watershed till depth were also important in determining correlations due to water interaction with surficial geology. Additionally, we found low NO3(-) :TP (N:P mass) values in seepage lakes (2.0 in winter, 1.9 in summer) compared to chain drainage lakes (169.4 in winter, 49.5 in summer) and headwater drainage lakes (97.0 in winter, 10.9 in summer), implying a high likelihood of future shifts in limitation patterns for seepage lakes. With increasing DOC and decreasing NO3(-) concentrations coinciding with decreases in acid deposition, there is reason to expect changes in nutrient dynamics in Adirondack lakes. Seepage lakes may become N-limited, while drainage lakes may become less P

  16. Contemporary doming of the Adirondack mountains: Further evidence from releveling

    USGS Publications Warehouse

    Isachsen, Y.W.

    1981-01-01

    The Adirondack Mountains constitute an anomalously large, domical uplift on the Appalachian foreland. The dome has a NNE-SSW axis about 190 km long, and an east-west dimension of about 140 km. It has a structural relief of at least 1600 m, and a local topographic relief of up to 1200 m. First-order leveling in 1955, and again in 1973 along a north-south line at the eastern margin of the Adirondack shows an uplift rate of 2.2 mm/yr at the latitude of the center of the dome and a subsidence rate of 2.8 mm/yr at the northern end of the line near the Canadian border. The net amount of arching along this releveled line is 9 cm ?? 2 cm (Isachsen, 1975). To test the idea that this arching represented an "edge effect" of contemporary doming of the Adirondacks as a whole, the National Geodetic Survey was encouraged to relevel a 1931 north-south line between Utica and Fort Covington (near the Canadian border) which crosses the center of the dome. The releveling showed that the mountain mass is undergoing contemporary domical uplift at a rate which reaches 3.7 mm/yr near the center of the dome (compare with 1 mm/yr for the Swiss Alps). Three other releveled lines in the area support this conclusion. ?? 1981.

  17. Manganese biogeochemistry in a small Adirondack forested lake watershed

    USGS Publications Warehouse

    Shanley, James B.

    1986-01-01

    In September and October 1981, manganese (Mn) concentrations and pH were intensively monitored in a small forested lake watershed in the west-central Adirondack Mountains, New York, during two large acidic storms (each approximately 5 cm rainfall, pH 4. 61 and 4. 15). The data were evaluated to identify biogeochemical pathways of Mn and to assess how these pathways are altered by acidic atmospheric inputs. Concentrations of Mn averaged 1. 1 mu g/L in precipitation and increased to 107 mu g/L in canopy throughfall, the enrichment reflecting active biological cycling of Mn. Rain pH and throughfall Mn were negatively correlated, suggesting that foliar leaching of Mn was enhanced by rainfall acidity. The pulse-like input of Mn to the forest floor in the high initial concentrations in throughfall (approximately 1000 mu g/L) did not affect Mn concentrations in soil water ( less than 20 mu g/L) or groundwater (usually less than 40 mu g/L), which varied little with time. In the inlet stream, Mn concentrations remained constant at 48 mu g/L as discharge varied from 1. 1 to 96 L/s. Manganese was retained in the vegetative cycle and regulated in the stream by adsorption in the soil organic horizon. The higher Mn levels in the stream may be linked to its high acidity (pH 4. 2-4. 3). Mixing of Mn-rich stream water with neutral lake water (pH 7. 0) caused precipitation of Mn and deposition in lake sediment.

  18. Acid precipitation effects on algal productivity and biomass in Adirondack Lakes. Final completion report

    SciTech Connect

    Hendrey, G.R.

    1982-12-01

    Relationships between phytoplankton communities and lake acidity in three Adirondack Mountain Lakes were studied at Woods Lake, Sagamore Lake (pH ca. 5.5), and Panther Lake (pH ca. 7.0). Numbers of phytoplankton species observed were Woods 45, Sagamore 55, and Panther 85, conforming to observations at many other sites that species numbers decrease with increasing acidity. The smaller plankton are relatively more important in the more acid lakes, Woods > Sagamore > Panther. This pattern could be determined by nutrient availability (lake acidification is suspected of leading to decreased availability of phosphorus). The amount of 14C-labelled dissolved photosynthate (14C-DOM), as a percent of total productivity, is ordered Woods > Sagamore > Panther.

  19. Drainage basin control of acid loadings to two Adirondack lakes

    NASA Astrophysics Data System (ADS)

    Booty, W. G.; Depinto, J. V.; Scheffe, R. D.

    1988-07-01

    Two adjacent Adirondack Park (New York) calibrated watersheds (Woods Lake and Cranberry Pond), which receive identical atmospheric inputs, generate significantly different unit area of watershed loading rates of acidity to their respective lakes. A watershed acidification model is used to evaluate the watershed parameters which are responsible for the observed differences in acid loadings to the lakes. The greater overall mean depth of overburden on Woods Lake watershed, which supplies a greater buffer capacity as well as a longer retention time of groundwater, appears to be the major factor responsible for the differences.

  20. A comparison of the temporally integrated monitoring of ecosystems and Adirondack Long Term-Monitoring programs in the Adirondack Mountain region of New Yrok

    EPA Science Inventory

    This paper compares lake chemistry in the Adirondack region of New York measured by the Temporally Integrated Monitoring of Ecosystems (TIME) and Adirondack Long-Term Monitoring (ALTM) programs by examining the data from six lakes common to both programs. Both programs were initi...

  1. Possible evidence for contemporary doming of the Adirondack Mountains, New York, and suggested implications for regional tectonics and seismicity

    USGS Publications Warehouse

    Isachsen, Y.W.

    1975-01-01

    at a rate far in excess of denudation. This inference leads to a consideration of other tectonic features which may be related in both the short and long term to such a postulated doming. One is the periodic occurrence of anomalous earthquake swarms located very near the geometric center of the Adirondack dome at Blue Mountain Lake, although horizontal rather than vertical compressive stresses have been shown to be dominant by Sbar and Sykes in 1973. Another, is the predominance of faults and topographic lineaments in the Adirondacks which parallel the long axis of the dome and are so remarkably well displayed in the infrared bands of ERTS-1 imagery. ?? 1975.

  2. PIXE Analysis of Aerosol and Soil Samples Collected in the Adirondack Mountains

    NASA Astrophysics Data System (ADS)

    Yoskowitz, Joshua; Ali, Salina; Nadareski, Benjamin; Labrake, Scott; Vineyard, Michael

    2014-09-01

    We have performed an elemental analysis of aerosol and soil samples collected at Piseco Lake in Upstate New York using proton induced X-ray emission spectroscopy (PIXE). This work is part of a systematic study of airborne pollution in the Adirondack Mountains. Of particular interest is the sulfur content that can contribute to acid rain, a well-documented problem in the Adirondacks. We used a nine-stage cascade impactor to collect the aerosol samples near Piseco Lake and distribute the particulate matter onto Kapton foils by particle size. The soil samples were also collected at Piseco Lake and pressed into cylindrical pellets for experimentation. PIXE analysis of the aerosol and soil samples were performed with 2.2-MeV proton beams from the 1.1-MV Pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. There are higher concentrations of sulfur at smaller particle sizes (0.25-1 μm), suggesting that it could be suspended in the air for days and originate from sources very far away. Other elements with significant concentrations peak at larger particle sizes (1-4 μm) and are found in the soil samples, suggesting that these elements could originate in the soil. The PIXE analysis will be described and the resulting data will be presented.

  3. Post-granulite facies fluid infiltration in the Adirondack Mountains

    SciTech Connect

    Morrison, J.; Valley, J.W.

    1988-06-01

    Granulite facies lithologies from the Adirondack Mountains of New York contain alteration assemblages composed dominantly of calcite +/- chlorite +/- sericite. These assemblages document fluid infiltration at middle to upper crustal levels. Cathodoluminescence of samples from the Marcy anorthosite massif indicates that the late fluid infiltration is more widespread than initially indicated by transmitted-light petrography alone. Samples that appear unaltered in transmitted light show extensive anastomosing veins of calcite (< 0.05 mm wide) along grain boundaries, in crosscutting fractures, and along mineral cleavages. The presence of the retrograde calcite documents paleopermeability in crystalline rocks and is related to the formation of high-density CO/sub 2/-rich fluid inclusions. Recognition of this process has important implications for studies of granulite genesis and the geophysical properties of the crust.

  4. Adirondack lakes survey: An interpretive analysis of fish communities and water chemistry, 1984--1987

    SciTech Connect

    Baker, J.P. , Raleigh, NC ); Gherini, S.A.; Munson, R.K. ); Christensen, S.W. ); Driscoll, C.T. ); Gallagher, J. ); Newton, R.M. ); Reckhow, K.H. ); Schofield, C.L. (Co

    1990-01-01

    The Adirondack Lakes Survey Corporation (ALSC) was formed as a cooperative effort of the New York State Department of Environmental Conservation and the Empire State Electric Energy Research Corporation to better characterize the chemical and biological status of Adirondack lakes. Between 1984 and 1987, the ALSC surveyed 1469 lakes within the Adirondack ecological zone. As a follow-up to the survey, the ALSC sponsored a series of interpretive analyses of the ALSC data base. The primary objectives of these analyses were as follows: Evaluate the influence of mineral acids (from acidic deposition) and nonmineral acids (natural organic acids) on lake pH levels; classify Adirondack lakes according to lake and watershed features expected to influence their responsiveness to changes in acidic deposition; evaluate the sensitivity of Adirondack lakes to changes in environmental conditions, such as changes in mineral acids or dissolved organic carbon concentrations; identify lake characteristics important in explaining the observed present-day status of fish communities in Adirondack lakes, in particular the relative importance of lake acidity; evaluate changes that have occurred over time in Adirondack fish communities and probable causes for these trends by using the available historical data on fish communities in the Adirondacks and the ALSC data base; and determine the degree to which the existing fish resource might be at risk from continued acidic deposition, or might recover if acidity levels were reduced. The basic approach examined relationships observed in the ALSC data base among watershed characteristics, lake chemistry, and fish status. Individual reports are processed separately for the data bases.

  5. PIXE Analysis of Atmospheric Aerosol Samples Collected in the Adirondack Mountains

    NASA Astrophysics Data System (ADS)

    Yoskowitz, Josh; Ali, Salina; Nadareski, Benjamin; Safiq, Alexandrea; Smith, Jeremy; Labrake, Scott; Vineyard, Michael

    2013-10-01

    We have performed an elemental analysis of atmospheric aerosol samples collected at Piseco Lake in Upstate New York using proton induced x-ray emission spectroscopy (PIXE). This work is part of a systematic study of airborne pollution in the Adirondack Mountains. Of particular interest is the sulfur content that can contribute to acid rain, a well-documented problem in the Adirondacks. We used a nine-stage cascade impactor to collect the samples and distribute the particulate matter onto Kapton foils by particle size. The PIXE experiments were performed with 2.2-MeV proton beams from the 1.1-MV pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. X-Ray energy spectra were measured with a silicon drift detector and analyzed with GUPIX software to determine the elemental concentrations of the aerosols. A broad range of elements from silicon to zinc were detected with significant sulfur concentrations measured for particulate matter between 0.25 and 0.5 μm in size. The PIXE analysis will be described and preliminary results will be presented.

  6. How much acidification has occurred in Adirondack region lakes (New York, USA) since preindustrial times

    SciTech Connect

    Cumming, B.F.; Smol, J.P.; Kingston, J.C.; Charles, D.F.; Birks, H.J.B.

    1992-01-01

    Preindustrial and present-day lake water pH, acid neutralizing capacity (ANC), total monomeric aluminum Al(sub m), and dissolved organic carbon (DOC) were inferred from the species composition of diatom and chrysophyte microfossils in the tops (present-day inferences) and bottoms (pre-1850 inferences) of sediment cores collected from a statistically selected set of Adirondack lakes. Results from the study lakes were extrapolated to a predefined target population of 675 low-alkalinity Adirondack region lakes. Estimates of preindustrial to present-day changes in lake water chemistry show that approximately 25-35% of the target population has acidified. The magnitude of acidification was greatest in the low-alkalinity lakes of the southwestern Adirondacks, an area with little geological ability to neutralize acidic deposition and receives the highest annual average rainfall in the region. The authors estimate that approximately 80% of the target population lakes with present-day measured pH = or < 5.2 and 30-45% of lakes with pH between 5.2 and 6.0 have undergone large declines in pH and ANC, and concomitant increases in Al(sub m). Estimated changes in (DOC) were small and show no consistent pattern in the acidified lakes. The study provides the first statistically based regional evaluation of the extent of lake acidification in the Adirondacks.

  7. Long-Term Trends in Trace Metals Concentrations in Sediment in Lakes in Adirondack Park, NY

    NASA Astrophysics Data System (ADS)

    Bari, A.; Judd, C. D.; Swami, K.; Ahmed, T.; Husain, L.

    2007-12-01

    The industrial Midwestern states consume large quantities of fossil fuel and emit large quantities of trace elements, SO2 and other chemicals. Owing to their long residence time these pollutants can be transported hundreds of miles downwind. These chemical species are removed from the atmosphere by wet and dry deposition and are ultimately deposited in lake sediments. Through the sedimentation process the pollution records can be stored for centuries. In this work we have attempted to retrieve the deposition of 25 trace elements for the past ~170 years by analyzing lake sediment cores from lakes located in the Adirondack Mountains. Sediment cores were collected from four lakes (Clear Pond, West Pine Pond, Bear Pond and Deer Pond) located in the Adirondack Park, NY. These lakes are at high altitude and some are inaccessible except by boat, and have minimum human activity (no motor boats, no camping and away from major roads). Coring was carried out by a gravity driven coring device. The cores were sectioned, weighed, freeze-dried, ground to a fine powder, and homogenized for analysis. The sediment cores were dated using 210Pb radioactive dating. The 137Cs activity was measured for an independent verification of 210Pb technique. Trace metals concentration were determined by microwave digestion method followed by inductively coupled plasma mass spectrometric (ICP-MS) analysis. The top sixteen sections of the West Pine Pond sediment core (representing from about 1835 to 2005) were analyzed for Sr, Ba, As, Se, Mo, Cd, Sn, Sb, Co, Ni, Cu, Ag,Ti, V, Cr, Mn, Fe, Zn, K, Na, Ca, Mg, Be, Tl, and Pb. During pre industrial era the concentrations of Pb, Se and Tl were very low and constant. Pb showed a sharp increase in concentration after around 1880 and a sharp decrease in concentration after about 1990. The concentration of Se increased slowly after pre industrial era. The concentrations of about eight of these elements were determined in quarterly composites of daily aerosol

  8. Relationships between surface sediment diatom assemblages and lakewater characteristics in Adirondack Lakes

    SciTech Connect

    Charles, D.F.

    1985-06-01

    Relationships between surface sediment diatom assemblages and lakewater characteristics were studied in 38 lakes in the Adirondack Mountains of northern New York. Most of the lakes are dilute, poorly buffered, and oligotrophic to mesotrophic. The diatom flora typical for circumneutral to acidic lakes. The purposes of this study were to identify the environmental factors most strongly related to the distributions of diatom taxa and the overall composition of diatom assemblages, and to derive equations to infer lakewater pH from diatom assemblage data. Relationships between diatom assemblages and environmental gradients were analyzed using reciprocal averaging ordination (RA). Correlations between Ra axis 1 and pH-related factors were strong. Correlations were weaker (but still statistically significant) with elevation, epilimnion temperature, and concentrations of SO/sub 4/, Cl, and Si. Total P, chlorophyll a, water color, and mean depth were not important in explaining differences among assemblages. Predictive equations were derived for inferring lakewater pH from diatom assemblage data. Agreement between predicted and measured pH was very good. These predictive relationships can be used to interpret stratigraphic diatom assemblages to reconstruct lake pH histories.

  9. Nitrate trends in the Adirondack Mountains, Northeastern US, 1993-2007

    EPA Science Inventory

    The Adirondack Mountains in New York State receive some of the highest rates of nitrogen deposition in the Northeastern U.S. Between 1993 and 2007, nitrogen deposition loads did not significantly change and average annual wet inorganic nitrogen deposition was 6 kg/ha (Figure 1)....

  10. Acidification in the Adirondacks: Defining the Biota in trophic Levels of 30 Chemically Diverse Acid-Impacted Lakes

    EPA Science Inventory

    The Adirondack Mountains in New York State have a varied surficial geology and chemically diverse surface waters that are among the most impacted by acid deposition in the U.S. No single Adirondack investigation has been comprehensive in defining the effects of acidification on ...

  11. Phytoplankton limitation by phosphorus and zooplankton grazing in an acidic Adirondack lake

    SciTech Connect

    Singer, R.; Evans, G.L.; Pratt, N.C.

    1984-08-01

    Lakes which are believed to have been acidified by atmospheric deposition of anthropogenic substances are known for their unusually high water clarity and low nutrient concentrations. Some evidence indicates that alterations in predator/prey relationships, an indirect effect of acidification, bring about the increase in water clarity. Enclosures were used to study the effects of phosphorus addition and zooplankton removal on the phytoplankton of an acidic lake in the Adirondack Mountains of New York. Fertilized enclosures had significantly lower alkalinities and contained significantly more dissolved oxygen after the incubation period than did unfertilized enclosures. The P concentration remained at or near the limit of detection in the unfertilized enclosures. The phytoplankton population bloomed after the addition of 80 micro g/liter of phosphate as KH/sub 2/PO/sub 4/. The response was measured by cell counts of the dominant phytoplankton. Chlamydomonas, and by changes in chlorophyll a concentration. About half the number of algal cells were present after the two week incubation when zooplankton were not removed, indicating that zooplankton herbivory can influence, but not totally control, the algal production. 46 references.

  12. Acidification in the Adirondacks: defining the biota in trophic levels of 30 chemically diverse acid-impacted lakes.

    PubMed

    Nierzwicki-Bauer, Sandra A; Boylen, Charles W; Eichler, Lawrence W; Harrison, James P; Sutherland, James W; Shaw, William; Daniels, Robert A; Charles, Donald F; Acker, Frank W; Sullivan, Timothy J; Momen, Bahram; Bukaveckas, Paul

    2010-08-01

    The Adirondack Mountains in New York State have a varied surficial geology and chemically diverse surface waters that are among the most impacted by acid deposition in the U.S. No single Adirondack investigation has been comprehensive in defining the effects of acidification on species diversity, from bacteria through fish, essential for understanding the full impact of acidification on biota. Baseline midsummer chemistry and community composition are presented for a group of chemically diverse Adirondack lakes. Species richness of all trophic levels except bacteria is significantly correlated with lake acid-base chemistry. The loss of taxa observed per unit pH was similar: bacterial genera (2.50), bacterial classes (1.43), phytoplankton (3.97), rotifers (3.56), crustaceans (1.75), macrophytes (3.96), and fish (3.72). Specific pH criteria were applied to the communities to define and identify acid-tolerant (pH<5.0), acid-resistant (pH 5.0-5.6), and acid-sensitive (pH>5.6) species which could serve as indicators. Acid-tolerant and acid-sensitive categories are at end-points along the pH scale, significantly different at P<0.05; the acid-resistant category is the range of pH between these end-points, where community changes continually occur as the ecosystem moves in one direction or another. The biota acid tolerance classification (batc) system described herein provides a clear distinction between the taxonomic groups identified in these subcategories and can be used to evaluate the impact of acid deposition on different trophic levels of biological communities.

  13. Impacts of Acidification and Potential Recovery on the Expected Value of Recreational Fisheries in Adirondack Lakes (USA).

    PubMed

    Caputo, Jesse; Beier, Colin M; Fakhraei, Habibollah; Driscoll, Charles T

    2017-01-03

    We estimated the potential economic value of recreational fisheries in lakes altered by acid pollution in the Adirondack Mountains (USA). We found that the expected value of recreational fisheries has been diminished because of acid deposition but may improve as lakes recover from acidification under low emissions scenarios combined with fish stocking. Fishery value increased with lake pH, from a low of $4.41 angler day(-1) in lakes with pH < 4.5, to a high of $38.40 angler day(-1) in lakes with pH > 6.5 that were stocked with trout species. Stocking increased the expected fishery value by an average of $11.50 angler day(-1) across the entire pH range of the lakes studied. Simulating the future long-term trajectory of a subset of lakes, we found that pH and expected fishery value increased over time in all future emissions scenarios. Differences in estimated value among pollution reduction scenarios were small (<$1 angler day(-1)) compared to fish stocking scenarios (>$4 angler day(-1)). Our work provides a basis for assessing the costs and benefits of emissions reductions and management efforts that can hasten recovery of the economic and cultural benefits of ecosystems degraded by chronic pollution.

  14. Geochemistry and origin of albite gneisses, northeastern Adirondack Mountains, New York

    NASA Astrophysics Data System (ADS)

    Whitney, Philip R.; Olmsted, James F.

    1988-08-01

    Albite gneisses containing up to 8.7 percent Na2O and as little as 0.1% K2O comprise a significant part of the Proterozoic Lyon Mountain Gneiss in the Ausable Forks Quadrangle of the northeastern Adirondacks, New York State. Two distinct types of albite gneisses are present. One is a trondhjemitic leucogneiss (LAG) consisting principally of albite (Ab95 Ab98) and quartz with minor magnetite and, locally, minor amounts of amphibole or acmiterich pyroxene. LAG probably originated by metamorphism of a rhyolitie or rhyodacitic ash-flow tuff with A-type geochemical affinities, following post-depositional analcitization in a saline or saline-alkaline environment. The other type is a mafic albite gneiss (MAG) containing albite and pyroxene along with 0 45 percent quartz, minor amphibole, and titanite. MAG locally displays pinstripe banding and contains albite (Ab98) megacrysts up to 5 cm across. Its precursor may have been a sediment composed of diagenetic analcite or albite, dolomite, and quartz. Both types of albite gneiss are interlayered with granitic gneisses (LMG) of variable composition derived from less altered tuffs. A potassium-rich (up to 9.7% K2O) microcline gneiss facies may have had a protolith rich in diagenetic K feldspar. We propose that the albite gneisses and associated granitic gneisses are the granulite-facies metamorphic equivalent of a bimodal, dominantly felsic, volcanic suite with minor intercalated sediments, probably including evaporites. The volcanics were erupted in an anorogenic setting, such as an incipient or failed intracontinental rift. Deposition took place in a closed-basin, playa lake environment, where diagenetic alteration resulted in redistribution of the alkalis and strong oxidation.

  15. Geochemistry and origin of albite gneisses, northeastern Adirondack Mountains, New York

    USGS Publications Warehouse

    Whitney, P.R.; Olmsted, J.F.

    1988-01-01

    Albite gneisses containing up to 8.7 percent Na2O and as little as 0.1% K2O comprise a significant part of the Proterozoic Lyon Mountain Gneiss in the Ausable Forks Quadrangle of the northeastern Adirondacks, New York State. Two distinct types of albite gneisses are present. One is a trondhjemitic leucogneiss (LAG) consisting principally of albite (Ab95-Ab98) and quartz with minor magnetite and, locally, minor amounts of amphibole or acmiterich pyroxene. LAG probably originated by metamorphism of a rhyolitie or rhyodacitic ash-flow tuff with A-type geochemical affinities, following post-depositional analcitization in a saline or saline-alkaline environment. The other type is a mafic albite gneiss (MAG) containing albite and pyroxene along with 0-45 percent quartz, minor amphibole, and titanite. MAG locally displays pinstripe banding and contains albite (Ab98) megacrysts up to 5 cm across. Its precursor may have been a sediment composed of diagenetic analcite or albite, dolomite, and quartz. Both types of albite gneiss are interlayered with granitic gneisses (LMG) of variable composition derived from less altered tuffs. A potassium-rich (up to 9.7% K2O) microcline gneiss facies may have had a protolith rich in diagenetic K feldspar. We propose that the albite gneisses and associated granitic gneisses are the granulite-facies metamorphic equivalent of a bimodal, dominantly felsic, volcanic suite with minor intercalated sediments, probably including evaporites. The volcanics were erupted in an anorogenic setting, such as an incipient or failed intracontinental rift. Deposition took place in a closed-basin, playa lake environment, where diagenetic alteration resulted in redistribution of the alkalis and strong oxidation. ?? 1988 Springer-Verlag.

  16. Spatial patterns of mercury in biota of Adirondack, New York lakes.

    PubMed

    Yu, Xue; Driscoll, Charles T; Montesdeoca, Mario; Evers, David; Duron, Melissa; Williams, Kate; Schoch, Nina; Kamman, Neil C

    2011-10-01

    We studied the spatial distribution patterns of mercury (Hg) in lake water, littoral sediments, zooplankton, crayfish, fish, and common loons in 44 lakes of the Adirondacks of New York State, USA, a region that has been characterized as a "biological Hg hotspot". Our study confirmed this pattern, finding that a substantial fraction of the lakes studied had fish and loon samples exceeding established criteria for human and wildlife health. Factors accounting for the spatial variability of Hg in lake water and biota were lake chemistry (pH, acid neutralizing capacity (ANC), percent carbon in sediments), biology (taxa presence, trophic status) and landscape characteristics (land cover class, lake elevation). Hg concentrations in zooplankton, fish and common loons were negatively associated with the lake water acid-base status (pH, ANC). Bioaccumulation factors (BAF) for methyl Hg (MeHg) increased from crayfish (mean log(10) BAF = 5.7), to zooplankton (5.9), to prey fish (6.2), to larger fish (6.3), to common loons (7.2). MeHg BAF values in zooplankton, crayfish, and fish (yellow perch equivalent) all increased with increasing lake elevation. Our findings support the hypothesis that bioaccumulation of MeHg at the base of the food chain is an important controller of Hg concentrations in taxa at higher trophic levels. The characteristics of Adirondack lake-watersheds (sensitivity to acidic deposition; significant forest and wetland land cover; and low nutrient inputs) contribute to elevated Hg concentrations in aquatic biota.

  17. Empirical Relationships Between Watershed Attributes and Headwater Lake Chemistry in the Adirondack Region

    SciTech Connect

    Hunsaker, C.T.

    1987-01-01

    Surface water acidification may be caused or influenced by both natural watershed processes and anthropogenic actions. Empirical models and observational data can be useful for identifying watershed attributes or processes that require further research or that should be considered in the development of process models. This study focuses on the Adirondack region of New York and has two purposes: to (1) develop empirical models that can be used to assess the chemical status of lakes for which no chemistry data exist and (2) determine on a regional scale watershed attributes that account for variability in lake pH and acid-neutralizing capacity (ANC). Headwater lakes, rather than lakes linked to upstream lakes, were selected for initial analysis. The Adirondacks Watershed Data Base (AWDB), part of the Acid Deposition Data Network maintained at Oak Ridge National Laboratory (ORNL), integrates data on physiography, bedrock, soils, land cover, wetlands, disturbances, beaver activity, land use, and atmospheric deposition with the water chemistry and morphology for the watersheds of 463 headwater lakes. The AWD8 facilitates both geographic display and statistical analysis of the data. The report, An Adirondack Watershed Data Base: Attribute and Mapping Information for Regional Acidic Deposition Studies (ORNL/TM--10144), describes the AWDB. Both bivariate (correlations and Wilcoxon and Kruskal-Wallis tests) and multivariate analyses were performed. Fifty-seven watershed attributes were selected as input variables to multiple linear regression and discriminant analysis. For model development -200 lakes for which pH and ANC data exist were randomly subdivided into a specification and a verification data set. Several indices were used to select models for predicting lake pH (31 variables) and ANC (27 variables). Twenty-five variables are common to the pH and ANC models: four lake morphology, nine soil/geology, eight land cover, three disturbance, and one watershed aspect. An

  18. Long-term pCO2 trends in Adirondack Lakes

    NASA Astrophysics Data System (ADS)

    Seekell, David A.; Gudasz, Cristian

    2016-05-01

    Lakes are globally significant sources of CO2 to the atmosphere. However, there are few temporally resolved records of lake CO2 concentrations and long-term patterns are poorly characterized. We evaluated annual trends in the partial pressure of CO2 (pCO2) based on chemical measurements from 31 Adirondack Lakes taken monthly over an 18 year period. All lakes were supersaturated with CO2 and were sources of CO2 to the atmosphere. There were significant pCO2 trends in 29% of lakes. The median magnitude of significant positive trends was 32.1 µatm yr-1. Overall, 52% of lakes had pCO2 trends greater than those reported for the atmosphere and ocean. Significant trends in lake pCO2 were attributable to regional recovery from acid deposition and changing patterns of ice cover. These results illustrate that lake pCO2 can respond rapidly to environmental change, but the lack of significant trend in 71% of lakes indicates substantial lake-to-lake variation in magnitude of response.

  19. Middle Proterozoic emplacement and deformation of metanorthosite and related rocks in the northeastern Marcy massif, Adirondack Mountains, New York

    SciTech Connect

    Fakundiny, R.H. ); Muller, P.D. . Dept. of Earth Sciences)

    1993-03-01

    Geologic mapping in the Elizabethtown and Mount Marcy 15 foot quadrangles in the northeastern Adirondack Mountains has shown that Middle Proterozoic anorthosite suite rocks of the Marcy massif were intruded in at least two temporally distinguishable episodes separated by a period of localized ductile shearing. Strain was concentrated in a 100 m to > 1 km thick zone consisting mainly of metamorphosed gabbroic anorthosite, ferrodiorite, and ferrosyenite gneiss with subordinate granite gneiss, calc-silicate gneiss, amphibolite, and marble. This zone of flat to steeply-dipping layered gneisses, designated the Elizabethtown ductile deformation zone (EDDZ) for exposures along Rt 9 south of Elizabethtown, appears to extend from Lake Champlain on the east to at least Lake Placid on the west. Its upper boundary is most clearly evident where it occurs in olivine metagabbro bodies of Jay and Iron Mountain. Massive metagabbro is sheared and recrystallized into amphibolite gneiss. The lower boundary of the zone is more difficult to map, but commonly lies within contaminated metamorphosed gabbroic anorthosite and ferrodiorite gneiss that characterize the margins of the massif in the area. Rocks of the EDDZ display pervasive mesoscopic S and LS fabrics, but exhibit totally recrystallized microtextures. Kinematic indicators such as winged porphyroclasts and S-C fabrics are sporadically developed and provide a regionally ambiguous sense of shear. The authors favor a regional extension origin for the fabrics. Mineral assemblages defining the EDDZ fabrics are consistent with granulite facies conditions during shear-zone development and suggest a lower crustal position. Mapping suggests that the younger anorthosite intrusions were mainly domical and generated a chaotic contact zone typified by block structure and dikes of ferrodiorite, ferromonzonite, and ferrosyenite.

  20. Persistent mortality of brook trout in episodically acidified streams of the Southwestern Adirondack Mountains, New York

    USGS Publications Warehouse

    Baldigo, Barry P.; Lawrence, G.; Simonin, H.

    2007-01-01

    Water chemistry, discharge, and mortality of caged brook trout Salvelinus fontinalis were characterized in six headwater streams in the southwestern Adirondack Mountains of New York during spring 2001-2003. Results were compared with mortality recorded during similar tests during 1984-1985, 1988-1990, and 1997 to assess contemporary relations between stream acidification and brook trout mortality, the effects of exposure duration on mortality, and the effects of decreased rates of acidic deposition on water quality and fish mortality. Water quality and mortality of caged, young-of-the-year brook trout were evaluated during 30-d exposure periods from mid-April to late May during the most recent tests. In 2001-2003, mortality ranged from 0% to 100% and varied among streams and years, depending on the timing of toxicity tests in relation to the annual snowmelt and on the ability of each watershed to neutralize acids and prevent acutely toxic concentrations of inorganic monomeric aluminum (Alim) during high-flow events. Mortality rates in 2001-2003 tests were highly variable but similar to those observed during earlier tests. This similarity suggests that stream water quality in the southwestern Adirondack Mountains has not changed appreciably over the past 20 years. Concentrations of Alim greater than 2.0 and 4.0 ??mol/L were closely correlated with low and high mortality rates, respectively, and accounted for 83% of the variation in mortality. Two to four days of exposure to Alim concentrations greater than 4.0 ??mol/L resulted in 50-100% mortality. The extended periods (as long as 6 months) during which Alim concentrations exceeded 2.0 and 4.0 ??mol/L in one or more streams, combined with the low tolerance of many other fish species to acid and elevated Al concentrations, indicate a high potential for damage to fish communities in these and other poorly buffered streams of the Northeast. ?? Copyright by the American Fisheries Society 2007.

  1. Evaluation of the recovery of Adirondack acid lakes by chemical manipulation

    SciTech Connect

    Depinto, J.V.; Edzwald, J.K.

    1982-06-01

    This study specifically addressed an evaluation of materials (calcium hydroxide and carbonate, agricultural limestone, fly ash, water treatment plant softening sludge, cement plant by-pass dust) for their neutralizing effectiveness and for establishing a neutral pH buffer system, and an evaluation of the effect of various lake recovery materials on algal growth. Laboratory continuous-flow microcosims were used as models to assess acid lake recovery. These models were filled with actual acid lake water over a layer of lake sediments, subjected to a given chemical treatment, and continuously fed water of selected quality (e.g., acid rain). A simulation of sediment-water-air kinetic interactions on a treated acid lake was obtained by careful monitoring of the microcosm chemical response. Agricultural limestone was determined to be the most appropriate material for acid lake recovery treatment based on its neutralizing properties, assessment of its potential impact on biota, its availability, and its relative cost: the results of this laboratory study suggest that full-scale recovery of an Adirondack acid lake is technically feasible. It is, however, recommended that an acid lake recovery field demonstration project be undertaken. 58 references, 36 figures, 29 tables.

  2. Long-term temporal trends and spatial patterns in the acid-base chemistry of lakes in the Adirondack region of New York in response to decreases in acidic deposition

    NASA Astrophysics Data System (ADS)

    Driscoll, Charles T.; Driscoll, Kimberley M.; Fakhraei, Habibollah; Civerolo, Kevin

    2016-12-01

    We examined the response of lake water chemistry in the Adirondack Mountains of New York State, USA to decreases in acid deposition. Striking declines in the concentrations and fluxes of sulfate and hydrogen ion in wet deposition have been observed since the late 1970s, while significant decreases in nitrate have been evident since the early 2000s. Decreases in estimated dry sulfur and nitrate deposition have also occurred in the Adirondacks, but with no change in dry to wet deposition ratios. These patterns follow long-term decreases in anthropogenic emissions of sulfur dioxide and nitrogen oxides in the U.S. over the same interval. All of the 48 lakes monitored through the Adirondack Long-Term Monitoring program since 1992 have exhibited significant declines in sulfate concentrations, consistent with reductions in atmospheric deposition of sulfur. Nitrate concentrations have also significantly diminished at variable rates in many (33 of 48) lakes. Decreases in concentrations of sulfate plus nitrate (48 of 48) in lakes have driven widespread increases in acid neutralizing capacity (ANC; 42 of 48) and lab pH (33 of 48), and decreases in the toxic fraction, inorganic monomeric Al (45 of 48). Coincident with decreases in acid deposition, concentrations of dissolved organic carbon (DOC) have also increased in some (29 of 48) lakes. While recovery from elevated acid deposition is evident across Adirondack lakes, highly sensitive and impacted mounded seepages lakes and thin till drainage lakes are recovering most rapidly. Future research might focus on how much additional recovery could be achieved given the current deposition relative to future deposition anticipated under the Clean Power Plan, ecosystem effects of increased mobilization of dissolved organic matter, and the influence of changing climate on recovery from acidification.

  3. Impacts of acidification on macroinvertebrate communities in streams of the western Adirondack Mountains, New York, USA

    USGS Publications Warehouse

    Baldigo, Barry P.; Lawrence, G.B.; Bode, R.W.; Simonin, H.A.; Roy, K.M.; Smith, A.J.

    2009-01-01

    Limited stream chemistry and macroinvertebrate data indicate that acidic deposition has adversely affected benthic macroinvertebrate assemblages in numerous headwater streams of the western Adirondack Mountains of New York. No studies, however, have quantified the effects that acidic deposition and acidification may have had on resident fish and macroinvertebrate communities in streams of the region. As part of the Western Adirondack Stream Survey, water chemistry from 200 streams was sampled five times and macroinvertebrate communities were surveyed once from a subset of 36 streams in the Oswegatchie and Black River Basins during 2003-2005 and evaluated to: (a) document the effects that chronic and episodic acidification have on macroinvertebrate communities across the region, (b) define the relations between acidification and the health of affected species assemblages, and (c) assess indicators and thresholds of biological effects. Concentrations of inorganic Al in 66% of the 200 streams periodically reached concentrations toxic to acid-tolerant biota. A new acid biological assessment profile (acidBAP) index for macroinvertebrates, derived from percent mayfly richness and percent acid-tolerant taxa, was strongly correlated (R2 values range from 0.58 to 0.76) with concentrations of inorganic Al, pH, ANC, and base cation surplus (BCS). The BCS and acidBAP index helped remove confounding influences of natural organic acidity and to redefine acidification-effect thresholds and biological-impact categories. AcidBAP scores indicated that macroinvertebrate communities were moderately or severely impacted by acidification in 44-56% of 36 study streams, however, additional data from randomly selected streams is needed to accurately estimate the true percentage of streams in which macroinvertebrate communities are adversely affected in this, or other, regions. As biologically relevant measures of impacts caused by acidification, both BCS and acidBAP may be useful

  4. Effects of acidic deposition and soil acidification on sugar maple trees in the Adirondack Mountains, New York

    USGS Publications Warehouse

    Sullivan, Timothy J.; Lawrence, Gregory B.; Bailey, Scott W.; McDonnell, Todd C.; Beier, Colin M.; Weathers, K.C.; McPherson, G.T.; Bishop, Daniel A.

    2013-01-01

    We documented the effects of acidic atmospheric deposition and soil acidification on the canopy health, basal area increment, and regeneration of sugar maple (SM) trees across the Adirondack region of New York State, in the northeastern United States, where SM are plentiful but not well studied and where widespread depletion of soil calcium (Ca) has been documented. Sugar maple is a dominant canopy species in the Adirondack Mountain ecoregion, and it has a high demand for Ca. Trees in this region growing on soils with poor acid–base chemistry (low exchangeable Ca and % base saturation [BS]) that receive relatively high levels of atmospheric sulfur and nitrogen deposition exhibited a near absence of SM seedling regeneration and lower crown vigor compared with study plots with relatively high exchangeable Ca and BS and lower levels of acidic deposition. Basal area increment averaged over the 20th century was correlated (p < 0.1) with acid–base chemistry of the Oa, A, and upper B soil horizons. A lack of Adirondack SM regeneration, reduced canopy condition, and possibly decreased basal area growth over recent decades are associated with low concentrations of nutrient base cations in this region that has undergone soil Ca depletion from acidic deposition.

  5. Effects of acidic deposition and soil acidification on sugar maple trees in the Adirondack Mountains, New York.

    PubMed

    Sullivan, T J; Lawrence, G B; Bailey, S W; McDonnell, T C; Beier, C M; Weathers, K C; McPherson, G T; Bishop, D A

    2013-11-19

    We documented the effects of acidic atmospheric deposition and soil acidification on the canopy health, basal area increment, and regeneration of sugar maple (SM) trees across the Adirondack region of New York State, in the northeastern United States, where SM are plentiful but not well studied and where widespread depletion of soil calcium (Ca) has been documented. Sugar maple is a dominant canopy species in the Adirondack Mountain ecoregion, and it has a high demand for Ca. Trees in this region growing on soils with poor acid-base chemistry (low exchangeable Ca and % base saturation [BS]) that receive relatively high levels of atmospheric sulfur and nitrogen deposition exhibited a near absence of SM seedling regeneration and lower crown vigor compared with study plots with relatively high exchangeable Ca and BS and lower levels of acidic deposition. Basal area increment averaged over the 20th century was correlated (p < 0.1) with acid-base chemistry of the Oa, A, and upper B soil horizons. A lack of Adirondack SM regeneration, reduced canopy condition, and possibly decreased basal area growth over recent decades are associated with low concentrations of nutrient base cations in this region that has undergone soil Ca depletion from acidic deposition.

  6. Trends in summer chemistry linked to productivity in lakes recovering from acid deposition in the Adirondack region of New York

    USGS Publications Warehouse

    Momen, B.; Lawrence, G.B.; Nierzwicki-Bauer, S. A.; Sutherland, J.W.; Eichler, L.W.; Harrison, J.P.; Boylen, C.W.

    2006-01-01

    The US Environmental Protection Agency established the Adirondack Effects Assessment Program (AEAP) to evaluate and monitor the status of biological communities in lakes in the Adirondack region of New York that have been adversely affected by acid deposition. This program includes chemical analysis of 30 lakes, sampled two to three times each summer. Results of trends analysis for lake chemistry and chlorophyll a (chlor a) are presented for 1994 to 2003, and a general comparison is made with recent results of the Adirondack Long-Term Monitoring (ALTM) Program, which included chemical analysis of all but two of these lakes (plus an additional 24 lakes) monthly, year-round for 1992-2004. Increases in pH were found in 25 of the 30 AEAP lakes (P < 0.05) and increases in acid-neutralizing capacity (ANC) were found in 12 of the 30 lakes (P < 0.05). Concentrations of both SO 42- and Mg 2+ decreased in 11 lakes (P < 0.05), whereas concentrations of NO 3- decreased in 20 lakes (P < 0.05). Concentrations of NH 4+ decreased in 10 lakes at a significance level of P < 0.05 and in three other lakes based on P < 0.1. Concentrations of inorganic and organic monomeric aluminum generally were below the reporting limit of 1.5 ??mol L-1, but decreases were detected in four and five lakes, respectively (P < 0.1). Concentrations of chlor a increased in seven lakes at a significance level of P < 0.05 and two lakes at a significance level of P < 0.1. A significant inverse correlation was also found between chlor a and NO 3- concentrations in nine lakes at a significance level of P < 0.05 and two lakes at a significance level of P < 0.1. Results of AEAP analysis of lake chemistry were similar to those of the ALTM Program, although decreases in SO 42- concentrations were more evident in the year-round ALTM record. Overall, the results suggest (a) a degree of chemical recovery from acidification during the summer, (b) an increase in phytoplankton productivity, and (c) a decreasing trend in

  7. Importance of within-lake processes in affecting the dynamics of dissolved organic carbon and dissolved organic and inorganic nitrogen in an Adirondack forested lake/watershed

    NASA Astrophysics Data System (ADS)

    Kang, Phil-Goo; Mitchell, Myron J.; McHale, Patrick J.; Driscoll, Charles T.; Inamdar, Shreeram; Park, Ji-Hyung

    2016-05-01

    Lakes nested in forested watersheds play an important role in mediating the concentrations and fluxes of dissolved organic matter. We compared long-term patterns of concentrations and fluxes of dissolved organic carbon (DOC) and dissolved organic (DON) and inorganic nitrogen (DIN) in aquatic ecosystems of the Arbutus Lake watershed to evaluate how a lake nested in a forested watershed affects the sources (e.g., production) and sinks (e.g., retention) of DOC and DON in the Adirondack Mountains of New York, USA. We observed no significant long-term changes of DOC and DON in the lake outlet since 1983 and 1994, respectively. However, the temporal patterns of DOC and DON concentrations in the lake inlet showed significant seasonality such as increases during the vegetation-growing season along with notable decreases in the dormant season. A comparison of mass balances between inlet and outlet for the period from 2000 to 2009 suggested that the lake was a sink of DOC (mean of influx minus outflux: +1140 mol C ha-1 yr-1). In contrast, the difference of discharge-weighted DON concentrations (mean of inlet minus outlet: -1.0 µmol N L-1) between inlet and outlet was much smaller than the discharge-weighted DOC concentrations (average of inlet minus outlet: + 87 µmol C L-1). DON fluxes showed considerable variation among years (mean of influx minus outflux: +8 mol N ha-1 yr-1; range of differences: -15 to 27 mol N ha-1 yr-1). DON exhibited low percent retention ((influx-outflux)/influx) (mean: 6.9 %, range: -34.8 to +31.2) compared to DOC (mean: 30.1 %, range: +9.2 to +44.1). The resultant increase of DON within the lake was closely linked with a net decrease of DIN through monthly Pearson correlation analysis, suggesting the importance of biotic factors in mediating lake DON dynamics. Our results show different relative retentions of DOC compared with DON, along with a larger retention of DIN than DON, suggesting that DOC and DON might display substantially different

  8. Increases in dissolved organic carbon accelerate loss of toxic Al in Adirondack lakes recovering from acidification

    USGS Publications Warehouse

    Lawrence, Gregory B.; Dukett, James E; Houck, Nathan; Snyder, Phillip; Capone, Susan B.

    2013-01-01

    Increasing pH and decreasing Al in surface waters recovering from acidification have been accompanied by increasing concentrations of dissolved organic carbon (DOC) and associated organic acids that partially offset pH increases and complicate assessments of recovery from acidification. To better understand the processes of recovery, monthly chemistry from 42 lakes in the Adirondack region, NY, collected from 1994 to 2011, were used to (1) evaluate long-term changes in DOC and associated strongly acidic organic acids and (2) use the base-cation surplus (BCS) as a chemical index to assess the effects of increasing DOC concentrations on the Al chemistry of these lakes. Over the study period, the BCS increased (p < 0.01) and concentrations of toxic inorganic monomeric Al (IMAl) decreased (p < 0.01). The decreases in IMAl were greater than expected from the increases in the BCS. Higher DOC concentrations that increased organic complexation of Al resulted in a decrease in the IMAl fraction of total monomeric Al from 57% in 1994 to 23% in 2011. Increasing DOC concentrations have accelerated recovery in terms of decreasing toxic Al beyond that directly accomplished by reducing atmospheric deposition of strong mineral acids.

  9. Target loads of atmospheric sulfur and nitrogen deposition for protection of acid sensitive aquatic resources in the Adirondack Mountains, New York

    USGS Publications Warehouse

    Sullivan, T.J.; Cosby, B.J.; Driscoll, C.T.; McDonnell, T.C.; Herlihy, A.T.; Burns, Douglas A.

    2012-01-01

    The dynamic watershed acid-base chemistry model of acidification of groundwater in catchments (MAGIC) was used to calculate target loads (TLs) of atmospheric sulfur and nitrogen deposition expected to be protective of aquatic health in lakes in the Adirondack ecoregion of New York. The TLs were calculated for two future dates (2050 and 2100) and three levels of protection against lake acidification (acid neutralizing capacity (ANC) of 0, 20, and 50 eq L -1). Regional sulfur and nitrogen deposition estimates were combined with TLs to calculate exceedances. Target load results, and associated exceedances, were extrapolated to the regional population of Adirondack lakes. About 30% of Adirondack lakes had simulated TL of sulfur deposition less than 50 meq m -2 yr to protect lake ANC to 50 eq L -1. About 600 Adirondack lakes receive ambient sulfur deposition that is above this TL, in some cases by more than a factor of 2. Some critical criteria threshold values were simulated to be unobtainable in some lakes even if sulfur deposition was to be decreased to zero and held at zero until the specified endpoint year. We also summarize important lessons for the use of target loads in the management of acid-impacted aquatic ecosystems, such as those in North America, Europe, and Asia. Copyright 2012 by the American Geophysical Union.

  10. Homogeneous /sup 18/O enrichment of the Marcy Anorthosite Massif, Adirondack Mountains, New York

    SciTech Connect

    Morrison, J.; Valley, J.W.

    1985-01-01

    The Marcy Anorthosite Massif in the Adirondack Mountains, New York, is a composite intrusion that was metamorphosed to granulite facies at approx. 1.1 Ga. The massif is dominantly anorthosite but ranges from anorthosite (1-10% mafics) to oxide-rich pyroxenite layers (up to 98% mafics). In the St Regis Quad (SRQ) systematic variations in the percentage of mafics (POM) roughly parallel the foliation and increase toward the contacts (Davis, 1971). In 47 SRQ samples studied the POM varies from 2-25%; garnet ranges from 0-11%, pyroxene from <1-16% and oxides from <1-8%. Percent phenocrysts varies between 1-80. The Port Kent-Westport Unit (PKW) and an associated hybrid unit show significantly greater textural variability. The POM Varies from 1-50%; garnet ranges from 0-18%, pyroxene from 0-15%, oxides from 0-3% and phenocrysts vary from 0-80%. A total of 28 unaltered plagioclase phenocrysts have been analyzed for delta/sup 18/O: in 13 SRQ samples delta/sup 18/O = 9.0-9.8 (x=9.4. sigma=0.2) and in 15 samples from the PKW and hybrid units values of delta/sup 18/O=8.5-10.5 (x=9.5.sigma0.5). No correlations exist between the modal parameters and delta/sup 18/O. The results from SRQ demonstrate an extreme homogeneity suggesting for the first time a pristine magmatic character which is supported by the virtual absence of metasedimentary inclusions. This contrasts with PKW where inclusions are common and delta/sup 18/O values are more heterogeneous. Further analyses will evaluate the possibility of an anomalous source region as a cause of the /sup 18/O enrichment in the anorthosite.

  11. Characterization of atmospheric aerosols in the Adirondack Mountains using PIXE, SEM/EDX, and Micro-Raman spectroscopies

    NASA Astrophysics Data System (ADS)

    Vineyard, M. F.; LaBrake, S. M.; Ali, S. F.; Nadareski, B. J.; Safiq, A. D.; Smith, J. W.; Yoskowitz, J. T.

    2015-05-01

    We are making detailed measurements of the composition of atmospheric aerosols collected in the Adirondack Mountains as a function of particle size using proton-induced X-ray emission, scanning electron microscopy with energy-dispersive X-ray spectroscopy, and Micro-Raman spectroscopy. These measurements provide valuable data to help identify the sources and understand the transport, transformation, and effects of airborne pollutants in upstate New York. Preliminary results indicate significant concentrations of sulfur in small particles that can travel great distances, and that this sulfur may be in the form of oxides that can contribute to acid rain.

  12. The effects of liming an Adirondack lake watershed on downstream water chemistry: Effects of liming on stream chemistry

    USGS Publications Warehouse

    Burns, Douglas A.

    1996-01-01

    Calcite treatment of chronically acidic lakes has improved fish habitat, but the effects on downstream water quality have not previously been examined. In this study, the spatial and temporal effects of watershed CaCO3 treatment on the chemistry of a lake outlet stream in the Adirondack Mountains of New York were examined. Before CaCO3 treatment, the stream was chronically acidic. During spring snowmelt before treatment, pH and acid-neutralizing capacity (ANC) in the outlet stream declined, and NO3- and inorganic monomeric aluminum (AlIM) concentrations increased sharply. During that summer, SO42- and NO3- concentrations decreased downstream, and dissolved organic carbon (DOC) concentrations and ANC increased, in association with the seasonal increase in decomposition of organic matter and the attendant SO42--reduction process. A charge-balance ANC calculation closely matched measured downstream changes in ANC in the summer and indicated that SO42- reduction was the major process contributing to summer increases in ANC. Increases in Ca2+ concentration and ANC began immediately after CaCO3 application, and within 3 months, exceeded their pretreatment values by more than 130 ??eq/L. Within 2 months after treatment, downstream decreases in Ca2+ concentration, ANC, and pH, were noted. Stream mass balances between the lake and the sampling site 1.5 km downstream revealed that the transport of all chemical constituents was dominated by conservative mixing with tributaries and ground water; however, non-conservative processes resulted in significant Ca2+ losses during the 13-month period after CaCO3 treatment. Comparison of substrate samples from the buffered outlet stream with those from its untreated tributaries showed that the percentage of cation-exchange sites occupied by Ca2+, as well as non-exchangeable Ca, were higher in the outlet-stream substrate than in tributary-stream substrate. Mass-balance data for Ca2+, H+, AlIM, and DOC revealed net downstream losses of

  13. Post-metamorphic fluid infiltration into granulites from the Adirondack Mountains, USA

    NASA Technical Reports Server (NTRS)

    Morrison, J.; Valley, John W.

    1988-01-01

    Post-metamorphic effects in the anorthosites of the Adirondacks, New York were described. Calcite-chlorite-sericite assemblages occur as veins, in disseminated form and as clots, and document retrograde fluid infiltration. These features are associated with late-state CO2-rich fluid inclusions. Stable isotope analyses of calcites indicates that the retrograde fluids interacted with meta-igneous and supracrustal lithologies, but the precise timing of the retrogression is as yet unknown.

  14. Long-term recovery of lakes in the Adirondack region of New York to decreases in acidic deposition

    NASA Astrophysics Data System (ADS)

    Waller, Kristin; Driscoll, Charles; Lynch, Jason; Newcomb, Dani; Roy, Karen

    2012-01-01

    After years of adverse impacts to the acid-sensitive ecosystems of the eastern United States, the Acid Rain Program and Nitrogen Budget Program were developed to control sulfur dioxide (SO 2) and nitrogen oxide (NO x) emissions through market-based cap and trade systems. We used data from the National Atmospheric Deposition Program's National Trends Network (NTN) and the U.S. EPA Temporally Integrated Monitoring of Ecosystems (TIME) program to evaluate the response of lake-watersheds in the Adirondack region of New York to changes in emissions of sulfur dioxide and nitrogen oxides resulting from the Acid Rain Program and the Nitrogen Budget Program. TIME is a long-term monitoring program designed to sample statistically selected subpopulations of lakes and streams across the eastern U.S. to quantify regional trends in surface water chemistry due to changes in atmospheric deposition. Decreases in wet sulfate deposition for the TIME lake-watersheds from 1991 to 2007 (-1.04 meq m -2-yr) generally corresponded with decreases in estimated lake sulfate flux (-1.46 ± 0.72 meq m -2-yr), suggesting declines in lake sulfate were largely driven by decreases in atmospheric deposition. Decreases in lake sulfate and to a lesser extent nitrate have generally coincided with increases in acid neutralizing capacity (ANC) resulting in shifts in lakes among ANC sensitivity classes. The percentage of acidic Adirondack lakes (ANC <0 μeq L -1) decreased from 15.5% (284 lakes) to 8.3% (152 lakes) since the implementation of the Acid Rain Program and the Nitrogen Budget Program. Two measures of ANC were considered in our analysis: ANC determined directly by Gran plot analysis (ANC G) and ANC calculated by major ion chemistry (ANC calc = CB - CA). While these two metrics should theoretically show similar responses, ANC calc (+2.03 μeq L -1-yr) increased at more than twice the rate as ANC G (+0.76 μeq L -1-yr). This discrepancy has important implications for assessments of lake recovery

  15. Historical Trends of Trace Metals in Lake Sediments From Adirondack Park, New York

    NASA Astrophysics Data System (ADS)

    Swami, K.; Judd, C. D.; Khan, A. J.; Bari, A.; Ahmed, T.; Husain, L.

    2009-05-01

    Burning of fossil fuel and many industrial operations emit large quantities of trace metals bearing aerosols along with other pollutants into the atmosphere. The pollutants can be transported thousands of kilometers downwind from their source. They are ultimately removed from the atmosphere by wet and dry deposition. Lake sediments can be used to provide a record of the environmental changes that have occurred in the past. In this study we determined the concentrations of trace metals from two lake sediment cores collected from Clear Pond and West Pine Pond, located in the Adirondack Park region in upstate New York. These lakes were chosen as they are remote and have minimum local sources of pollution. The cores were sliced into thin sections, dried and weighed. The sediment cores were dated using the 210Pb technique. The top sixteen sections of the West Pine Pond and Clear Pond sediment represented deposits from about 1821 to 2005, and around 1880 to 2007, respectively. A microwave digestion procedure was used to separate trace metals from organic matter and silicates. The trace element concentrations were determined using inductively coupled plasma mass spectrometry (ICP-MS). These samples were analyzed for As, Se, Mo, Cd, Sn, Sb, Co, Ni, Cu, Ag, Ti, V, Cr, Mn, Fe, Zn, K, Na, Ca, Mg, Ba, Sr, Be, Hg, Tl, and Pb. The lithophilic elements Ba, Sr, Al, Ti, K, Na, Ca, Mg and Sr showed little increase over the entire period studied in both lakes. Vanadium and Cr showed little increase in the West Pine Pond core (1.2 and 1.4 times the preindustrial level, resp.), but increased more (1.7 and 2.0, resp.) in the Clear Pond core. The elements As, Se, Mo, Cd, Sn, Sb, Co, Ni, Cu, Mn, Fe, Zn, Hg, Tl, V and Pb showed significant increases due to anthropogenic inputs. Lead showed the greatest increase over the preindustrial baseline concentration, a 12-fold increase in Clear Pond and 24-fold in West Pine Pond. Large increases were also seen in Se and Hg ranging from (2.4 to 10

  16. A monitor for continuous measurement of temperature, pH, and conductance of wet precipitation: Preliminary results from the Adirondack Mountains, New York

    USGS Publications Warehouse

    Johnsson, P.A.; Reddy, M.M.

    1990-01-01

    This report describes a continuous wet-only precipitation monitor designed by the U.S. Geological Survey to record variations in rainfall temperature, pH, and specific conductance at 1-min intervals over the course of storms. Initial sampling in the Adirondack Mountains showed that rainfall acidity varied over the course of summer storms, with low initial pH values increasing as storm intensity increased.This report describes a continuous wet-only precipitation monitor designed by the U.S. Geological Survey to record variations in rainfall temperature, pH, and specific conductance at 1-min intervals over the course of storms. Initial sampling in the Adirondack Mountains showed that rainfall acidity varied over the course of summer storms, with low initial pH values increasing as storm intensity increased.

  17. Evidence for multiple metamorphic events in the Adirondack Mountains, N. Y

    SciTech Connect

    McLelland, J.; Lochhead, A.; Vyhnal, C.

    1988-05-01

    Field evidence consisting of: (1) rotated, foliated xenoliths, (2) country rock foliation truncated by isoclinally folded igneous intrusions bearing granulite facies assemblages document one, or more, early dynamothermal event(s) of regional scale and high grade. Early metamorphism resulted in pronounced linear and planar fabric throughout the Adirondacks and preceded the emplacement of the anorthosite-mangerite-charnockite-granite-alaskite (AMCA) suite which contains xenoliths of the metamorphosed rocks. Olivine metagabbros, believed to be approximately contemporaneous with the AMCA-suite, also crosscut and contain xenoliths of, strongly foliated metasediments. These intrusive rocks caused contact metamorphism in the metasediments which locally exhibit both anatectite and restite assemblages. Subsequently, this already complex framework underwent three phases of folding, including an early recumbent isoclinical event, and was metamorphosed to granulite facies P,T conditions. The age of the early metamorphism cannot yet be narrowly constrained, but isotopic results suggest that it may be as young as approx. 1200 Ma or older than approx. 1420 Ma. U-Pb zircon ages indicate emplacement of the AMCA-(metagabbro)-suite in the interval 1160-1130 Ma and place the peak of granulite facies metamorphism between 1070-1025 Ma. The anorogenic character of the AMCA-suite, and the occurrence of metadiabase dike swarms within it, are further evidence of the separate nature of the metamorphic events that precede and postdate AMCA emplacement.

  18. Adirondack Under the Microscope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image was taken by the Mars Exploration Rover Spirit front hazard-identification camera after the rover's first post-egress drive on Mars Sunday, Jan. 15, 2004. Engineers drove the rover approximately 3 meters (10 feet) from the Columbia Memorial Station toward the first rock target, seen in the foreground. The football-sized rock was dubbed Adirondack because of its mountain-shaped appearance. Scientists have begun using the microscopic imager instrument at the end of the rover's robotic arm to examine the rock and understand how it formed.

  19. Hydrogeologic Controls on Lake Level at Mountain Lake, Virginia

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

    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

  20. Food Web Topology in High Mountain Lakes

    PubMed Central

    Sánchez-Hernández, Javier; Cobo, Fernando; Amundsen, Per-Arne

    2015-01-01

    Although diversity and limnology of alpine lake systems are well studied, their food web structure and properties have rarely been addressed. Here, the topological food webs of three high mountain lakes in Central Spain were examined. We first addressed the pelagic networks of the lakes, and then we explored how food web topology changed when benthic biota was included to establish complete trophic networks. We conducted a literature search to compare our alpine lacustrine food webs and their structural metrics with those of 18 published lentic webs using a meta-analytic approach. The comparison revealed that the food webs in alpine lakes are relatively simple, in terms of structural network properties (linkage density and connectance), in comparison with lowland lakes, but no great differences were found among pelagic networks. The studied high mountain food webs were dominated by a high proportion of omnivores and species at intermediate trophic levels. Omnivores can exploit resources at multiple trophic levels, and this characteristic might reduce competition among interacting species. Accordingly, the trophic overlap, measured as trophic similarity, was very low in all three systems. Thus, these alpine networks are characterized by many omnivorous consumers with numerous prey species and few consumers with a single or few prey and with low competitive interactions among species. The present study emphasizes the ecological significance of omnivores in high mountain lakes as promoters of network stability and as central players in energy flow pathways via food partitioning and enabling energy mobility among trophic levels. PMID:26571235

  1. Food Web Topology in High Mountain Lakes.

    PubMed

    Sánchez-Hernández, Javier; Cobo, Fernando; Amundsen, Per-Arne

    2015-01-01

    Although diversity and limnology of alpine lake systems are well studied, their food web structure and properties have rarely been addressed. Here, the topological food webs of three high mountain lakes in Central Spain were examined. We first addressed the pelagic networks of the lakes, and then we explored how food web topology changed when benthic biota was included to establish complete trophic networks. We conducted a literature search to compare our alpine lacustrine food webs and their structural metrics with those of 18 published lentic webs using a meta-analytic approach. The comparison revealed that the food webs in alpine lakes are relatively simple, in terms of structural network properties (linkage density and connectance), in comparison with lowland lakes, but no great differences were found among pelagic networks. The studied high mountain food webs were dominated by a high proportion of omnivores and species at intermediate trophic levels. Omnivores can exploit resources at multiple trophic levels, and this characteristic might reduce competition among interacting species. Accordingly, the trophic overlap, measured as trophic similarity, was very low in all three systems. Thus, these alpine networks are characterized by many omnivorous consumers with numerous prey species and few consumers with a single or few prey and with low competitive interactions among species. The present study emphasizes the ecological significance of omnivores in high mountain lakes as promoters of network stability and as central players in energy flow pathways via food partitioning and enabling energy mobility among trophic levels.

  2. Lead Speciation in remote Mountain Lakes

    NASA Astrophysics Data System (ADS)

    Plöger, A.; van den Berg, C. M. G.

    2003-04-01

    In natural waters trace metals can become complexed by organic matter. This complexation can change the geochemistry of the metals by preventing them being scavenged, thereby increasing their residence time in the water column. The chemical speciation of trace metals also affects the bioavalability and their toxicological impact on organisms. It is therefore important to determine the chemical speciation of trace metals as well as their concentrations. Mountain lakes have been less studied in the past than other lakes- partly because of their remoteness and partly because they were perceived to be unpolluted and undisturbed. But work so far on mountain lakes has shown that most sites are affected and threatened, for example by transboundary air pollutants like trace metals. One of the important features that distinguishes these lakes from lowland lakes at similar latitudes is the fact that they may be isolated from the atmosphere for six months or more during the winter by a thick ice cover. Also, as these lakes are remote from direct anthropogenic influences, they reflect the regional distribution of pollutants transferred via the atmosphere. For this work, under the framework of the EMERGE (European Mountain lake Ecosystems: Regionalisation, diaGnostic and socio-economic Evaluation) programme, two remote mountain lakes have been studied in detail, with water sampling taking place at different times of the year to investigate possible seasonal differences in lead concentrations and speciation. Results so far have shown that lead-complexing ligand concentrations are in excess to dissolved lead concentrations, indicating that dissolved lead probably occurs fully complexed in these lakes. Therefore the toxic fraction is likely to be less than the dissolved lead concentration. Also, lead concentrations at the time of the spring thaw are higher than autumn concentrations just before ice cover, indicating that a significant proportion of fallout onto the lake catchment

  3. Efficacy of environmental DNA to detect and quantify Brook Trout populations in headwater streams of the Adirondack Mountains, New York

    USGS Publications Warehouse

    Baldigo, Barry P.; Sporn, Lee Ann; George, Scott D.; Ball, Jacob

    2016-01-01

    Environmental DNA (eDNA) analysis is rapidly evolving as a tool for monitoring the distributions of aquatic species. Detection of species’ populations in streams may be challenging because the persistence time for intact DNA fragments is unknown and because eDNA is diluted and dispersed by dynamic hydrological processes. During 2015, the DNA of Brook Trout Salvelinus fontinalis was analyzed from water samples collected at 40 streams across the Adirondack region of upstate New York, where Brook Trout populations were recently quantified. Study objectives were to evaluate different sampling methods and the ability of eDNA to accurately predict the presence and abundance of resident Brook Trout populations. Results from three-pass electrofishing surveys indicated that Brook Trout were absent from 10 sites and were present in low (<100 fish/0.1 ha), moderate (100–300 fish/0.1 ha), and high (>300 fish/0.1 ha) densities at 9, 11, and 10 sites, respectively. The eDNA results correctly predicted the presence and confirmed the absence of Brook Trout at 85.0–92.5% of the study sites; eDNA also explained 44% of the variability in Brook Trout population density and 24% of the variability in biomass. These findings indicate that eDNA surveys will enable researchers to effectively characterize the presence and abundance of Brook Trout and other species’ populations in headwater streams across the Adirondack region and elsewhere.

  4. Sensitivity of Stream Methyl Hg Concentrations to Environmental Change in the Adirondack Mountains of New York, USA

    NASA Astrophysics Data System (ADS)

    Burns, D. A.; Riva-Murray, K.; Nystrom, E.; Millard, G.; Driscoll, C. T.

    2014-12-01

    The Adirondacks of New York have high levels of mercury (Hg) bioaccumulation as demonstrated by a region-wide fish consumption advisory for children and women who may become pregnant. The source of this Hg is atmospheric deposition that originates from regional, continental, and global emissions. Soils in the region have large Hg stores equivalent to several decades of atmospheric deposition suggesting that the processes controlling Hg transport from soils to surface waters may greatly affect Hg concentrations and loads in surface waters. Furthermore, Hg can be converted to its neuro-toxic methyl form (MeHg), particularly in riparian and wetland soils where biogeochemical conditions favor net methylation. We measured MeHg concentrations during 33 months at Fishing Brook, a 65 km2 catchment in the upper Hudson River basin in the Adirondacks. Seasonal variation in stream MeHg concentrations was more than tenfold, consistent with temperature-driven variation in net methylation rates in soils and sediment. These data also indicate greater than twofold annual variation in stream MeHg concentrations among the three monitored growing seasons. The driest growing season had the lowest MeHg concentrations, and these values were greater during the two wetter growing seasons. We hypothesize that contact of the riparian water table with abundant organic matter and MeHg stored in the shallowest soil horizons is a dominant control on MeHg transport to the stream. An empirical model was developed that accounted for 81% of the variation in stream MeHg concentrations. Water temperature and the length of time the simulated riparian water table remained in the shallow soil were key predictive variables, highlighting the sensitivity of MeHg to climatic variation. Future changes in other factors such as Hg emissions and deposition and acid deposition will likely also influence stream MeHg concentrations and loads. For example, lime application to an Adirondack stream to increase pH and

  5. SKY LAKES ROADLESS AREA AND MOUNTAIN LAKES WILDERNESS, OREGON.

    USGS Publications Warehouse

    Smith, James G.; Benham, John R.

    1984-01-01

    Based on a mineral survey of the Sky Lakes Roadless Area and the Mountain Lakes Wilderness, Oregon, the areas have little or no promise for the occurrence of metallic-mineral resources or geothermal energy resources. Nonmetallic resources exist in the areas, but other areas outside the roadless area and wilderness also contain resources of volcanic cinders, scoria, ash, breccia, and sand and gravel which are easier to obtain and closer to markets. The roadless area and wilderness are not geologically favorable for metallic deposits, or for coal, oil, or gas resources.

  6. Compositional controls on spinel clouding and garnet formation in plagioclase of olivine metagabbros, Adirondack Mountains, New York

    USGS Publications Warehouse

    McLelland, J.M.; Whitney, P.R.

    1980-01-01

    Olivine metagabbros from the Adirondacks usually contain both clear and spinel-clouded plagioclase, as well as garnet. The latter occurs primarily as the outer rim of coronas surrounding olivine and pyroxene, and less commonly as lamellae or isolated grains within plagioclase. The formation of garnet and metamorphic spinel is dependent upon the anorthite content of the plagioclase. Plagioclase more sodic than An38??2 does not exhibit spinel clouding, and garnet rarely occurs in contact with plagioclase more albitic than An36??4. As a result of these compositional controls, the distribution of spinel and garnet mimics and visually enhances original igneous zoning in plagioclase. Most features of the arrangement of clear (unclouded) plagioclase, including the shells or moats of clear plagioclase which frequently occur inside the garnet rims of coronas, can be explained on the basis of igneous zoning. The form and distribution of the clear zones may also be affected by the metamorphic reactions which have produced the coronas, and by redistribution of plagioclase in response to local volume changes during metamorphism. ?? 1980 Springer-Verlag.

  7. Mercury methylation in Sphagnum moss mats and its association with sulfate-reducing bacteria in an acidic Adirondack forest lake wetland.

    PubMed

    Yu, Ri-Qing; Adatto, Isaac; Montesdeoca, Mario R; Driscoll, Charles T; Hines, Mark E; Barkay, Tamar

    2010-12-01

    Processes leading to the bioaccumulation of methylmercury (MeHg) in northern wetlands are largely unknown. We have studied various ecological niches within a remote, acidic forested lake ecosystem in the southwestern Adirondacks, NY, to discover that mats comprised of Sphagnum moss were a hot spot for mercury (Hg) and MeHg accumulation (190.5 and 18.6 ng g⁻¹ dw, respectively). Furthermore, significantly higher potential methylation rates were measured in Sphagnum mats as compared with other sites within Sunday Lake's ecosystem. Although MPN estimates showed a low biomass of sulfate-reducing bacteria (SRB), 2.8 × 10⁴ cells mL⁻¹ in mat samples, evidence consisting of (1) a twofold stimulation of potential methylation by the addition of sulfate, (2) a significant decrease in Hg methylation in the presence of the sulfate reduction inhibitor molybdate, and (3) presence of dsrAB-like genes in mat DNA extracts, suggested that SRB were involved in Hg methylation. Sequencing of dsrB genes indicated that novel SRB, incomplete oxidizers including Desulfobulbus spp. and Desulfovibrio spp., and syntrophs dominated the sulfate-reducing guild in the Sphagnum moss mat. Sphagnum, a bryophyte dominating boreal peatlands, and its associated microbial communities appear to play an important role in the production and accumulation of MeHg in high-latitude ecosystems.

  8. Acid-base characteristics of the Grass Pond watershed in the Adirondack Mountains of New York State, USA: interactions among soil, vegetation and surface waters

    NASA Astrophysics Data System (ADS)

    McEathron, K. M.; Mitchell, M. J.; Zhang, L.

    2013-07-01

    Grass Pond watershed is located within the southwestern Adirondack Mountain region of New York State, USA. This region receives some of the highest rates of acidic deposition in North America and is particularly sensitive to acidic inputs due to many of its soils having shallow depths and being generally base poor. Differences in soil chemistry and tree species between seven subwatersheds were examined in relation to acid-base characteristics of the seven major streams that drain into Grass Pond. Mineral soil pH, stream water BCS (base-cation surplus) and pH exhibited a positive correlation with sugar maple basal area (p = 0.055; 0.48 and 0.39, respectively). Black cherry basal area was inversely correlated with stream water BCS, ANC (acid neutralizing capacity)c and NO3- (p = 0.23; 0.24 and 0.20, respectively). Sugar maple basal areas were positively associated with watershed characteristics associated with the neutralization of atmospheric acidic inputs while in contrast, black cherry basal areas showed opposite relationships to these same watershed characteristics. Canonical correspondence analysis indicated that black cherry had a distinctive relationship with forest floor chemistry apart from the other tree species, specifically a strong positive association with forest floor NH4, while sugar maple had a distinctive relationship with stream chemistry variables, specifically a strong positive association with stream water ANCc, BCS and pH. Our results provide evidence that sugar maple is acid-intolerant or calciphilic tree species and also demonstrate that black cherry is likely an acid-tolerant tree species.

  9. WILD CATTLE MOUNTAIN AND HEART LAKE ROADLESS AREAS, CALIFORNIA.

    USGS Publications Warehouse

    Muffler, L.J. Patrick; Denton, David K.

    1984-01-01

    The results of geologic, geochemical, and geophysical surveys in Wild Cattle Mountain and Heart Lake Roadless Areas in California indicate little promise for the occurrence of metallic, nonmetallic, or fossil fuel resources. However, Wild Cattle Mountain Roadless Area and part of Heart Lake Roadless Area lie in Lassen Known Geothermal Resources Area, and noncompetitive geothermal lease applications have been filed on much of the rest of Heart Lake Roadless Area. Both areas are adjacent to Lassen Volcanic National Park. Geochemical and geologic data indicate that the thermal manifestations in the Park and at Growler and Morgan Hot Springs just southwest of Wild Cattle Mountain Roadless Area are part of the same large geothermal system. Consequently, the entire Wild Cattle Mountain Roadless Area and part of the Heart Lake Roadless Area have a substantiated geothermal resource potential; the rest of the Heart Lake Roadless Area has a probable geothermal resource potential.

  10. Effects of acid deposition on dissolution of carbonate stone during summer storms in the Adirondack Mountains, New York, 1987-89

    USGS Publications Warehouse

    Schuster, Paul F.; Reddy, Michael M.; Sherwood, S.I.

    1994-01-01

    This study is part of a long-term research program designed to identify and quantify acid rain damage to carbonate stone. Acidic deposition accelerates the dissolution of carbonate-stone monuments and building materials. Sequential sampling of runoff from carbonate-stone (marble) and glass (reference) microcatchments in the Adirondack Mountains in New York State provided a detailed record of the episodic fluctuations in rain rate and runoff chemistry during individual summer storms. Rain rate and chemical concentrations from carbonate-stone and glass runoff fluctuated three to tenfold during storms. Net calcium-ion concentrations from the carbonatestone runoff, a measure of stone dissolution, typically fluctuated twofold during these storms. High net sulfate and net calcium concentrations in the first effective runoff at the start of a storm indicated that atmospheric pollutants deposited on the stone surface during dry periods formed calcium sulfate minerals, an important process in carbonate stone dissolution. Dissolution of the carbonate stone generally increased up to twofold during coincident episodes of low rain rate (less than 5 millimeters per hour) and decreased rainfall (glass runoff) pH (less than 4.0); episodes of high rain rate (cloudbursts) were coincident with a rapid increase in rainfall pH and also a rapid decrease in the dissolution of carbonate-stone. During a storm, it seems the most important factors causing increased dissolution of carbonate stone are coincident periods of low rain rate and decreased rainfall pH. Dissolution of the carbonate stone decreased slightly as the rain rate exceeded about 5 millimeters per hour, probably in response to rapidly increasing rainfall pH during episodes of high rain rate and shorter contact time between the runoff and the stone surface. High runoff rates resulting from cloudbursts remove calcium sulfate minerals formed during dry periods prior to storms and also remove dissolution products formed in large

  11. Influence of dietary carbon on mercury bioaccumulation in streams of the Adirondack Mountains of New York and the Coastal Plain of South Carolina, USA.

    PubMed

    Riva-Murray, Karen; Bradley, Paul M; Chasar, Lia C; Button, Daniel T; Brigham, Mark E; Scudder Eikenberry, Barbara C; Journey, Celeste A; Lutz, Michelle A

    2013-01-01

    We studied lower food webs in streams of two mercury-sensitive regions to determine whether variations in consumer foraging strategy and resultant dietary carbon signatures accounted for observed within-site and among-site variations in consumer mercury concentration. We collected macroinvertebrates (primary consumers and predators) and selected forage fishes from three sites in the Adirondack Mountains of New York, and three sites in the Coastal Plain of South Carolina, for analysis of mercury (Hg) and stable isotopes of carbon (δ(13)C) and nitrogen (δ(15)N). Among primary consumers, scrapers and filterers had higher MeHg and more depleted δ(13)C than shredders from the same site. Variation in δ(13)C accounted for up to 34 % of within-site variation in MeHg among primary consumers, beyond that explained by δ(15)N, an indicator of trophic position. Consumer δ(13)C accounted for 10 % of the variation in Hg among predatory macroinvertebrates and forage fishes across these six sites, after accounting for environmental aqueous methylmercury (MeHg, 5 % of variation) and base-N adjusted consumer trophic position (Δδ(15)N, 22 % of variation). The δ(13)C spatial pattern within consumer taxa groups corresponded to differences in benthic habitat shading among sites. Consumers from relatively more-shaded sites had more enriched δ(13)C that was more similar to typical detrital δ(13)C, while those from the relatively more-open sites had more depleted δ(13)C. Although we could not clearly attribute these differences strictly to differences in assimilation of carbon from terrestrial or in-channel sources, greater potential for benthic primary production at more open sites might play a role. We found significant variation among consumers within and among sites in carbon source; this may be related to within-site differences in diet and foraging habitat, and to among-site differences in environmental conditions that influence primary production. These observations

  12. Influence of dietary carbon on mercury bioaccumulation in streams of the Adirondack Mountains of New York and the Coastal Plain of South Carolina, USA

    USGS Publications Warehouse

    Riva-Murray, Karen; Bradley, Paul M.; Chasar, Lia C.; Button, Daniel T.; Brigham, Mark E.; Eikenberry, Barbara C. Scudder; Journey, Celeste; Lutz, Michelle A.

    2013-01-01

    We studied lower food webs in streams of two mercury-sensitive regions to determine whether variations in consumer foraging strategy and resultant dietary carbon signatures accounted for observed within-site and among-site variations in consumer mercury concentration. We collected macroinvertebrates (primary consumers and predators) and selected forage fishes from three sites in the Adirondack Mountains of New York, and three sites in the Coastal Plain of South Carolina, for analysis of mercury (Hg) and stable isotopes of carbon (δ13C) and nitrogen (δ15N). Among primary consumers, scrapers and filterers had higher MeHg and more depleted δ13C than shredders from the same site. Variation in δ13C accounted for up to 34 % of within-site variation in MeHg among primary consumers, beyond that explained by δ15N, an indicator of trophic position. Consumer δ13C accounted for 10 % of the variation in Hg among predatory macroinvertebrates and forage fishes across these six sites, after accounting for environmental aqueous methylmercury (MeHg, 5 % of variation) and base-N adjusted consumer trophic position (Δδ15N, 22 % of variation). The δ13C spatial pattern within consumer taxa groups corresponded to differences in benthic habitat shading among sites. Consumers from relatively more-shaded sites had more enriched δ13C that was more similar to typical detrital δ13C, while those from the relatively more-open sites had more depleted δ13C. Although we could not clearly attribute these differences strictly to differences in assimilation of carbon from terrestrial or in-channel sources, greater potential for benthic primary production at more open sites might play a role. We found significant variation among consumers within and among sites in carbon source; this may be related to within-site differences in diet and foraging habitat, and to among-site differences in environmental conditions that influence primary production. These observations suggest that different

  13. 62. Lake Pleasant with snow in the Bradshaw Mountains. Photographer ...

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

    62. Lake Pleasant with snow in the Bradshaw Mountains. Photographer Mark Durben. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  14. Acid Rain Effects on Adirondack Streams - Results from the 2003-05 Western Adirondack Stream Survey (the WASS Project)

    USGS Publications Warehouse

    Lawrence, Gregory B.; Roy, Karen M.; Baldigo, Barry P.; Simonin, Howard A.; Passy, Sophia I.; Bode, Robert W.; Capone, Susan B.

    2009-01-01

    Traditionally lakes have been the focus of acid rain assessments in the Adirondack region of New York. However, there is a growing recognition of the importance of streams as environmental indicators. Streams, like lakes, also provide important aquatic habitat, but streams more closely reflect acid rain effects on soils and forests and are more prone to acidification than lakes. Therefore, a large-scale assessment of streams was undertaken in the drainage basins of the Oswegatchie and Black Rivers; an area of 4,585 km2 in the western Adirondack region where acid rain levels tend to be highest in New York State.

  15. A fractal-based approach to lake size-distributions

    NASA Astrophysics Data System (ADS)

    Seekell, David A.; Pace, Michael L.; Tranvik, Lars J.; Verpoorter, Charles

    2013-02-01

    The abundance and size distribution of lakes is critical to assessing the role of lakes in regional and global biogeochemical processes. Lakes are fractal but do not always conform to the power law size-distribution typically associated with fractal geographical features. Here, we evaluate the fractal geometry of lakes with the goal of explaining apparently inconsistent observations of power law and non-power law lake size-distributions. The power law size-distribution is a special case for lakes near the mean elevation. Lakes in flat regions are power law distributed, while lakes in mountainous regions deviate from power law distributions. Empirical analyses of lake size data sets from the Adirondack Mountains in New York and the flat island of Gotland in Sweden support this finding. Our approach provides a unifying framework for lake size-distributions, indicates that small lakes cannot dominate total lake surface area, and underscores the importance of regional hypsometry in influencing lake size-distributions.

  16. Adirondack's Inner Self

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This spectrum - the first taken of a rock on another planet - reveals the different iron-containing minerals that makeup the martian rock dubbed Adirondack. It shows that Adirondack is a type of volcanic rock known as basalt. Specifically, the rock is what is called olivine basalt because in addition to magnetite and pyroxene, two key ingredients of basalt, it contains a mineral called olivine. This data was acquired by Spirit's Moessbauer spectrometer before the rover developed communication problems with Earth on the 18th martian day, or sol, of its mission.

  17. Eskers as an aid to the understanding of deglaciation in the Northern Adirondacks

    SciTech Connect

    King, G.S. . Geology Dept.)

    1993-03-01

    Eskers in the Northern Adirondack Mountains of New York State have been examined in order to gain a better understanding of their origin, their relationship to other glacial landforms, and to determine the relative timing of their formation. Ultimately, it is hoped that eskers can be used to construct a model of the former ice sheet for the region. Cross sections and longitudinal profiles were constructed to give a better understanding of esker form. Subsequent fieldwork was designed to confirm and compliment these morphometric analyses. The sedimentology of an esker and adjacent fan was logged and interpreted. The spatial relations between the eskers, fans, and delta complexes were identified. Results indicate that the eskers of the Northern Adirondack Mountains formed at different stages in the retreat of the ice sheet and are not related to an integrated subglacial drainage system. The presence of a lacustrine fan at the south end of the St. Regis Esker indicates that a glacial lake was present at the ice sheet margin and delimits an ice marginal position. The morphology and distribution of eskers may be useful as an indicator in the timing of continental deglaciation of northern New York State. Research for this project was funded by a University of Dayton Research Council Grant to D. Pair.

  18. High bacterial diversity in epilithic biofilms of oligotrophic mountain lakes.

    PubMed

    Bartrons, Mireia; Catalan, Jordi; Casamayor, Emilio O

    2012-11-01

    Benthic microbial biofilms attached to rocks (epilithic) are major sites of carbon cycling and can dominate ecosystem primary production in oligotrophic lakes. We studied the bacterial community composition of littoral epilithic biofilms in five connected oligotrophic high mountain lakes located at different altitudes by genetic fingerprinting and clone libraries of the 16S rRNA gene. Different intra-lake samples were analyzed, and consistent changes in community structure (chlorophyll a and organic matter contents, and bacterial community composition) were observed along the altitudinal gradient, particularly related with the location of the lake above or below the treeline. Epilithic biofilm genetic fingerprints were both more diverse among lakes than within lakes and significantly different between montane (below the tree line) and alpine lakes (above the tree line). The genetic richness in the epilithic biofilm was much higher than in the plankton of the same lacustrine area studied in previous works, with significantly idiosyncratic phylogenetic composition (specifically distinct from lake plankton or mountain soils). Data suggest the coexistence of aerobic, anaerobic, phototrophic, and chemotrophic microorganisms in the biofilm, Bacteroidetes and Cyanobacteria being the most important bacterial taxa, followed by Alpha-, Beta-, Gamma-, and Deltaproteobacteria, Chlorobi, Planctomycetes, and Verrucomicrobia. The degree of novelty was especially high for epilithic Bacteroidetes, and up to 50 % of the sequences formed monophyletic clusters distantly related to any previously reported sequence. More than 35 % of the total sequences matched at <95 % identity to any previously reported 16S rRNA gene, indicating that alpine epilithic biofilms are unexplored habitats that contain a substantial degree of novelty within a short geographical distance. Further research is needed to determine whether these communities are involved in more biogeochemical pathways than

  19. Forest blowdown and lake acidification

    SciTech Connect

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

    1990-01-01

    The authors examine the role of forest blowdown in lake acidification. The approach combines geographic information systems (GIS) and digital remote sensing with traditional field methods. The methods of analysis consist of direct observation, interpretation of satellite imagery and aerial photographs, and statistical comparison of two geographical distributions-one representing forest blow-down and another representing lake chemistry. Spatial and temporal associations between surface water pH and landscape disturbance are strong and consistent in the Adirondack Mountains of New York. In 43 Adirondack Mountain watersheds, lake pH is associated with the percentage of the watershed area blown down and with hydrogen ion deposition (Spearman rank correlation coefficients of {minus}0.67 and {minus}0.73, respectively). Evidence of a temporal association is found at Big Moose Lake and Jerseyfield Lake in New York and the Lygners Vider Plateau of Sweden. They conclude that forest blowdown facilities the acidification of some lakes by altering hydrologic pathways so that waters (previously acidified by acid deposition and/or other sources) do not experience the neutralization normally available through contact with subsurface soils and bedrock. Increased pipeflow is suggested as a mechanism that may link the biogeochemical impacts of forest blowdown to lake chemistry.

  20. Adirondack Under the Microscope-2

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This overhead look at the martian rock dubbed Adirondack was captured by the Mars Exploration Rover Spirit's panoramic camera. It shows the approximate region where the rover's microscopic imager began its first close-up inspection.

  1. NCCN Mountain Lakes Monitoring Strategy: Guidelines to Resolution

    USGS Publications Warehouse

    Hoffman, Robert L.; Huff, Mark H.

    2008-01-01

    The North Coast and Cascades Network (NCCN) Inventory and Monitoring Program provides funds to its Network Parks to plan and implement the goals and objectives of the National Park Services? (NPS) Inventory and Monitoring (I&M) Program. The primary purpose of the I&M program is to develop and implement a long-term monitoring program in each network. The purpose of this document is to describe the outcome of a meeting held to find solutions to obstacles inhibiting development of a unified core design and methodology for mountain lake monitoring.

  2. Assessment of lake sensitivity to acidic deposition in national parks of the Rocky Mountains

    USGS Publications Warehouse

    Nanus, L.; Williams, M.W.; Campbell, D.H.; Tonnessen, K.A.; Blett, T.; Clow, D.W.

    2009-01-01

    The sensitivity of high-elevation lakes to acidic deposition was evaluated in five national parks of the Rocky Mountains based on statistical relations between lake acid-neutralizing capacity concentrations and basin characteristics. Acid-neutralizing capacity (ANC) of 151 lakes sampled during synoptic surveys and basin-characteristic information derived from geographic information system (GIS) data sets were used to calibrate the statistical models. The explanatory basin variables that were considered included topographic parameters, bedrock type, and vegetation type. A logistic regression model was developed, and modeling results were cross-validated through lake sampling during fall 2004 at 58 lakes. The model was applied to lake basins greater than 1 ha in area in Glacier National Park (n = 244 lakes), Grand Teton National Park (n = 106 lakes), Great Sand Dunes National Park and Preserve (n = 11 lakes), Rocky Mountain National Park (n = 114 lakes), and Yellowstone National Park (n = 294 lakes). Lakes that had a high probability of having an ANC concentration 3000 m, with 80% of the catchment bedrock having low buffering capacity. The modeling results indicate that the most sensitive lakes are located in Rocky Mountain National Park and Grand Teton National Park. This technique for evaluating the lake sensitivity to acidic deposition is useful for designing long-term monitoring plans and is potentially transferable to other remote mountain areas of the United States and the world.

  3. Biological studies of atmospheric deposition impact on biota in Kola North Mountain Lakes, Russia

    SciTech Connect

    Yakovlev, V.; Sharov, A.; Vandysh, O.

    1996-12-31

    In the framework of the AL:PE projects, biological studies of phyto-, zooplankton and zoobenthos communities of a small lakes situated in Chuna tundra and Chibiny mountains in Murmansk region were performed in 1993-1995. The lakes are the typical oligotrophic mountain lakes. In the Chibiny lake phytoplankton were presented mostly by species from rock catchment area. Summer phytoplankton state in the lakes showed no acidification in 1993-1995. However, the great number dead cells of acid tolerance diatoms, such as Tabellaria flocculosa found in the Chuna lake in summer period, may indicate a presence of acid episodes. Zooplankton of the lakes is typical for high oligotrophic mountain lakes. However, lack of the acid sensitive daphniidae cladocerans seems to be a result of acidification effects. There were no significant relationships between benthic invertebrates species composition and present water acidity of the lakes. The typical for mountain lakes taxa (Prodiamesinae chironomids, stone flies and mayflies) were found in lake shore and streams. Despite the only little evidence of damage in biota, the further biological studies would be useful for long-term monitoring of the mountain lakes.

  4. High diversity of protistan plankton communities in remote high mountain lakes in the European Alps and the Himalayan mountains

    PubMed Central

    Kammerlander, Barbara; Breiner, Hans-Werner; Filker, Sabine; Sommaruga, Ruben; Sonntag, Bettina; Stoeck, Thorsten

    2015-01-01

    We analyzed the genetic diversity (V4 region of the 18S rRNA) of planktonic microbial eukaryotes in four high mountain lakes including two remote biogeographic regions (the Himalayan mountains and the European Alps) and distinct habitat types (clear and glacier-fed turbid lakes). The recorded high genetic diversity in these lakes was far beyond of what is described from high mountain lake plankton. In total, we detected representatives from 66 families with the main taxon groups being Alveolata (55.0% OTUs97%, operational taxonomic units), Stramenopiles (34.0% OTUs97%), Cryptophyta (4.0% OTUs97%), Chloroplastida (3.6% OTUs97%) and Fungi (1.7% OTUs97%). Centrohelida, Choanomonada, Rhizaria, Katablepharidae and Telonema were represented by <1% OTUs97%. Himalayan lakes harbored a higher plankton diversity compared to the Alpine lakes (Shannon index). Community structures were significantly different between lake types and biogeographic regions (Fisher exact test, P < 0.01). Network analysis revealed that more families of the Chloroplastida (10 vs 5) and the Stramenopiles (14 vs 8) were found in the Himalayan lakes than in the Alpine lakes and none of the fungal families was shared between them. Biogeographic aspects as well as ecological factors such as water turbidity may structure the microbial eukaryote plankton communities in such remote lakes. PMID:25764458

  5. High diversity of protistan plankton communities in remote high mountain lakes in the European Alps and the Himalayan mountains.

    PubMed

    Kammerlander, Barbara; Breiner, Hans-Werner; Filker, Sabine; Sommaruga, Ruben; Sonntag, Bettina; Stoeck, Thorsten

    2015-04-01

    We analyzed the genetic diversity (V4 region of the 18S rRNA) of planktonic microbial eukaryotes in four high mountain lakes including two remote biogeographic regions (the Himalayan mountains and the European Alps) and distinct habitat types (clear and glacier-fed turbid lakes). The recorded high genetic diversity in these lakes was far beyond of what is described from high mountain lake plankton. In total, we detected representatives from 66 families with the main taxon groups being Alveolata (55.0% OTUs 97%, operational taxonomic units), Stramenopiles (34.0% OTUs 97%), Cryptophyta (4.0% OTUs 97%), Chloroplastida (3.6% OTUs 97%) and Fungi (1.7% OTUs 97%). Centrohelida, Choanomonada, Rhizaria, Katablepharidae and Telonema were represented by <1% OTUs 97%. Himalayan lakes harbored a higher plankton diversity compared to the Alpine lakes (Shannon index). Community structures were significantly different between lake types and biogeographic regions (Fisher exact test, P < 0.01). Network analysis revealed that more families of the Chloroplastida (10 vs 5) and the Stramenopiles (14 vs 8) were found in the Himalayan lakes than in the Alpine lakes and none of the fungal families was shared between them. Biogeographic aspects as well as ecological factors such as water turbidity may structure the microbial eukaryote plankton communities in such remote lakes.

  6. 77 FR 75186 - Notice of Closure, Target Shooting Public Safety Closure on the Lake Mountains in Utah County, UT

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-19

    ... Bureau of Land Management Notice of Closure, Target Shooting Public Safety Closure on the Lake Mountains... approximately 900 acres of public land on the Lake Mountains in Utah County, Utah, to recreational target... Lake Mountains area. DATES: This target shooting closure within the described area will remain...

  7. 77 FR 31379 - Hart Mountain National Antelope Refuge, Lake County, OR; Draft Comprehensive Conservation Plan...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-25

    ... Fish and Wildlife Service Hart Mountain National Antelope Refuge, Lake County, OR; Draft Comprehensive... to revise the comprehensive conservation plan (CCP) for Hart Mountain National Antelope Refuge... regulations. Hart Mountain National Antelope Refuge The Refuge's approved boundary encompasses 277,893...

  8. Spirit Takes a Turn for Adirondack

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This rear hazard-identification camera image looks back at the circular tracks made in the martian soil when the Mars Exploration Rover Spirit drove about 3 meters (10 feet) toward the mountain-shaped rock called Adirondack, Spirit's first rock target. Spirit made a series of arcing turns totaling approximately 1 meter (3 feet). It then turned in place and made a series of short, straightforward movements totaling approximately 2 meters (6.5 feet). The drive took about 30 minutes to complete, including time stopped to take images. The two rocks in the upper left corner of the image are called 'Sashimi' and 'Sushi.' In the upper right corner is a portion of the lander, now known as the Columbia Memorial Station.

  9. Long-term water temperature reconstructions from mountain lakes with different catchment and morphometric features

    PubMed Central

    Luoto, Tomi P.; Nevalainen, Liisa

    2013-01-01

    Long-term water temperature records are necessary for better understanding climate change impacts on freshwaters. We reconstruct summer water temperatures from three climatically sensitive mountain lakes in Austria using paleolimnological methods aiming to examine long-term thermal dynamics and lakes' responses to regional climate variability since the Little Ice Age. Our results indicate divergent trends for the lakes. In two of the lakes, which are located at the sunny southern slope of mountains, water temperature has increased several degrees concurrent with the observed air temperature increase. In contrast, no change is observed in the reconstructed water temperatures of a shaded lake, located at the northern slope, where also the ecological and thermal changes are most subtle. The results indicate the importance of cold water inputs, such as snowmelt and groundwater, on lakes' thermal conditions and suggest that watershed characteristics and lake stratification play a major role in defining the lake-specific thermal regime. PMID:23965988

  10. Development stages of hazardous mountain lakes and simulation of their outbursts (Central Caucasus, Russia; Sichuan mountain region, China).

    NASA Astrophysics Data System (ADS)

    Kidyaeva, Vera; Krylenko, Inna; Chernomorets, Sergey; Petrakov, Dmitry

    2013-04-01

    The importance of mountain lakes studies is related to the increasing threat of natural disasters, associated with lake outbursts and debris flows formation, because of population growth on exposed areas. The outburst hazard has not been sufficiently researched, there is a lack of data because of the lakes inaccessibility and remote sensing data is usually not detailed enough. The main scientific topics include assessment of outburst possibility and further simulation of possible outbursts scenarios. There are two types of mountain lakes: glacial (cirque, cirque-moraine, barrier-moraine, glacial-barrier, etc.) lakes and barrier (landslide, rockfall, debris flow, etc.) lakes. The first type was studied in the Central Caucasus (Russia), and the second type - in the Sichuan mountain region (China). The group of scientists, including authors, has been monitoring glacial lakes in the Mnt. Elbrus area for more than ten years. The unique data were collected, including detailed hydrological characteristics of more than ten lakes (water level dynamics, temperature, morphometrical characteristics, water balance components, etc.). Outbursts of at least three glacial lakes were observed. Hydrological characteristics of landslide Tangjiashan Lake were collected with Chinese colleagues during field studies in 2010 and 2011 years. Analysis of the collected data was used to understand the outburst mechanisms, formation factors, dam breaking factors, development stages of mountain lakes. Statistical methods of analysis in this case can be applied with some limitations because of the lack of sufficient monitoring objects, and therefore the results has been verified by experts. All types of possible outbursts mechanisms were divided by the authors into five groups: geomorphologic (caused by changes in lake dams), seismic, or geodynamic (caused by seiches, waves from rockfalls, landslides), glacial (caused by breaks in impounding glaciers, ice floating and melting), water

  11. Morphology and biology of Cyclops scutifer Sars, 1863 in high mountain lakes of East Siberia (including Lake Amut)

    NASA Astrophysics Data System (ADS)

    Sheveleva, Natalya G.; Itigilova, Mydygma Ts.; Chananbaator, Ayushcuren

    2016-04-01

    Data on zooplankton from 13 high-mountain lakes of East Siberia have shown that the Holarctic copepod Cyclops scutifer Sars, 1863 dominates among crustaceans. In July, its abundance comprised 64%-98% of the total plankton fauna in the pelagial of these lakes, approximately 30% in the littoral zone and 10% in small northern thermokarst lakes. Biometric measurements and morphological descriptions based on scanning microscope images are supplemented by the data on its geographic distribution and phenology.

  12. Effects of recreational flow releases on natural resources of the Indian and Hudson Rivers in the Central Adirondack Mountains, New York, 2004-06

    USGS Publications Warehouse

    Baldigo, Barry P.; Mulvihill, C.I.; Ernst, A.G.; Boisvert, B.A.

    2011-01-01

    The U.S. Geological Survey (USGS), the New York State Department of Environmental Conservation (NYSDEC), and Cornell University carried out a cooperative 2-year study from the fall of 2004 through the fall of 2006 to characterize the potential effects of recreational-flow releases from Lake Abanakee on natural resources in the Indian and Hudson Rivers. Researchers gathered baseline information on hydrology, temperature, habitat, nearshore wetlands, and macroinvertebrate and fish communities and assessed the behavior and thermoregulation of stocked brown trout in study reaches from both rivers and from a control river. The effects of recreational-flow releases (releases) were assessed by comparing data from affected reaches with data from the same reaches during nonrelease days, control reaches in a nearby run-of-the-river system (the Cedar River), and one reach in the Hudson River upstream from the confluence with the Indian River. A streamgage downstream from Lake Abanakee transmitted data by satellite from November 2004 to November 2006; these data were used as the basis for developing a rating curve that was used to estimate discharges for the study period. River habitat at most study reaches was delineated by using Global Positioning System and ArcMap software on a handheld computer, and wetlands were mapped by ground-based measurements of length, width, and areal density. River temperature in the Indian and Hudson Rivers was monitored continuously at eight sites during June through September of 2005 and 2006; temperature was mapped in 2005 by remote imaging made possible through collaboration with the Rochester Institute of Technology. Fish communities at all study reaches were surveyed and characterized through quantitative, nearshore electrofishing surveys. Macroinvertebrate communities in all study reaches were sampled using the traveling-kick method and characterized using standard indices. Radio telemetry was used to track the movement and persistence of

  13. American Fisheries Society 136th Annual Meeting Lake Placid, NY 10-14 September, 2006

    USGS Publications Warehouse

    Einhouse, D.; Walsh, M.G.; Keeler, S.; Long, J.M.

    2005-01-01

    The New York Chapter of the American Fisheries Society and the New York State Department of Environmental Conservation invite you to experience the beauty of New York's famous Adirondack Park as the American Fisheries Society (AFS) convenes its 136th Annual Meeting in the legendary Olympic Village of Lake Placid, NY, 10-14 September 2006. Our meeting theme "Fish in the Balance" will explore the interrelation between fish, aquatic habitats, and man, highlighting the challenges facing aquatic resource professionals and the methods that have been employed to resolve conflicts between those that use or have an interest in our aquatic resources. As fragile as it is beautiful, the Adirondack Region is the perfect location to explore this theme. Bordered by Mirror Lake and its namesake, Lake Placid, the Village of Lake Placid has small town charm, but all of the conveniences that a big city would provide. Whether its reliving the magic of the 1980 hockey team's "Miracle on Ice" at the Lake Placid Olympic Center, getting a panoramic view of the Adirondack high peaks from the top of the 90 meter ski jumps, fishing or kayaking in adjacent Mirror Lake, hiking a mountain trail, or enjoying a quiet dinner or shopping excursion in the various shops and restaurants that line Main Street, Lake Placid has something for everyone.

  14. Assessment of lake sensitivity to acidic deposition in national parks of the Rocky Mountains.

    PubMed

    Nanus, L; Williams, M W; Campbell, D H; Tonnessen, K A; Blett, T; Clow, D W

    2009-06-01

    The sensitivity of high-elevation lakes to acidic deposition was evaluated in five national parks of the Rocky Mountains based on statistical relations between lake acid-neutralizing capacity concentrations and basin characteristics. Acid-neutralizing capacity (ANC) of 151 lakes sampled during synoptic surveys and basin-characteristic information derived from geographic information system (GIS) data sets were used to calibrate the statistical models. The explanatory basin variables that were considered included topographic parameters, bedrock type, and vegetation type. A logistic regression model was developed, and modeling results were cross-validated through lake sampling during fall 2004 at 58 lakes. The model was applied to lake basins greater than 1 ha in area in Glacier National Park (n = 244 lakes), Grand Teton National Park (n = 106 lakes), Great Sand Dunes National Park and Preserve (n = 11 lakes), Rocky Mountain National Park (n = 114 lakes), and Yellowstone National Park (n = 294 lakes). Lakes that had a high probability of having an ANC concentration <100 microeq/L, and therefore sensitive to acidic deposition, are located in basins with elevations >3000 m, with <30% of the catchment having northeast aspect and with >80% of the catchment bedrock having low buffering capacity. The modeling results indicate that the most sensitive lakes are located in Rocky Mountain National Park and Grand Teton National Park. This technique for evaluating the lake sensitivity to acidic deposition is useful for designing long-term monitoring plans and is potentially transferable to other remote mountain areas of the United States and the world.

  15. Water quality of potential reference lakes in the Arkansas Valley and Ouachita Mountain ecoregions, Arkansas.

    PubMed

    Justus, Billy; Meredith, Bradley

    2014-06-01

    This report describes a study to identify reference lakes in two lake classifications common to parts of two level III ecoregions in western Arkansas-the Arkansas Valley and Ouachita Mountains. Fifty-two lakes were considered. A screening process that relied on land-use data was followed by reconnaissance water-quality sampling, and two lakes from each ecoregion were selected for intensive water-quality sampling. Our data suggest that Spring Lake is a suitable reference lake for the Arkansas Valley and that Hot Springs Lake is a suitable reference lake for the Ouachita Mountains. Concentrations for five nutrient constituents--orthophosphorus, total phosphorus, total kjeldahl nitrogen, total nitrogen, and total organic carbon--were lower at Spring Lake on all nine sampling occasions and transparency measurements at Spring Lake were significantly deeper than measurements at Cove Lake. For the Ouachita Mountains ecoregion, water quality at Hot Springs Lake slightly exceeded that of Lake Winona. The most apparent water-quality differences for the two lakes were related to transparency and total organic carbon concentrations, which were deeper and lower at Hot Springs Lake, respectively. Our results indicate that when nutrient concentrations are low, transparency may be more valuable for differentiating between lake water quality than chemical constituents that have been useful for distinguishing between water-quality conditions in mesotrophic and eutrophic settings. For example, in this oligotrophic setting, concentrations for chlorophyll a can be less than 5 μg/L and diurnal variability that is typically associated with dissolved oxygen in more productive settings was not evident.

  16. Water quality of potential reference lakes in the Arkansas Valley and Ouachita Mountain ecoregions, Arkansas

    USGS Publications Warehouse

    Justus, B.G.; Meredith, Bradley J.

    2014-01-01

    This report describes a study to identify reference lakes in two lake classifications common to parts of two level III ecoregions in western Arkansas—the Arkansas Valley and Ouachita Mountains. Fifty-two lakes were considered. A screening process that relied on land-use data was followed by reconnaissance water-quality sampling, and two lakes from each ecoregion were selected for intensive water-quality sampling. Our data suggest that Spring Lake is a suitable reference lake for the Arkansas Valley and that Hot Springs Lake is a suitable reference lake for the Ouachita Mountains. Concentrations for five nutrient constituents—orthophosphorus, total phosphorus, total kjeldahl nitrogen, total nitrogen, and total organic carbon—were lower at Spring Lake on all nine sampling occasions and transparency measurements at Spring Lake were significantly deeper than measurements at Cove Lake. For the Ouachita Mountains ecoregion, water quality at Hot Springs Lake slightly exceeded that of Lake Winona. The most apparent water-quality differences for the two lakes were related to transparency and total organic carbon concentrations, which were deeper and lower at Hot Springs Lake, respectively. Our results indicate that when nutrient concentrations are low, transparency may be more valuable for differentiating between lake water quality than chemical constituents that have been useful for distinguishing between water-quality conditions in mesotrophic and eutrophic settings. For example, in this oligotrophic setting, concentrations for chlorophyll a can be less than 5 μg/L and diurnal variability that is typically associated with dissolved oxygen in more productive settings was not evident.

  17. Responses of Ambystoma gracile to the removal of introduced nonnative fish from a mountain lake

    USGS Publications Warehouse

    Hoffman, Robert L.; Larson, Gary L.; Samora, B.

    2004-01-01

    Introduced, nonnative brook trout (Salvelinus fontinalis) were removed from a mountain lake in Mount Rainier National Park, Washington, to examine the capacity of native Ambystoma gracile (Northwestern Salamander) in the lake to respond to the intentional removal of fish. Temporal trends (N) were calculated for A. gracile larvae/neotene and egg mass relative abundances in the Fish Removal and an adjacent Fishless Lake. The diel and spatial patterns of A. gracile in the lakes were also enumerated during time-intervals of fish presence in and after fish removal from the Fish Removal Lake. Sixty-six fish were removed from the Fish Removal Lake. The Ns for relative abundances in the Fish Removal Lake were positive for the study period and indicated that the number of larvae/neotenes and egg masses observed in the lake increased concurrent with the removal and extirpation of fish from the lake. Numbers of larvae/neotenes and egg masses observed in the Fishless Lake varied annually, but no overall positive or negative trends were evident during the study. Ambystoma gracile in the Fish Removal Lake, during fish presence, were predominantly nocturnal and located in the shallow, structurally complex nearshore area of the lake. After fish were removed, the number of A. gracile observed in the lake increased, especially during the day and in the deeper, less structurally complex offshore area of the lake. Fishless Lake A. gracile were readily observed day and night in all areas of the lake throughout the study. The A. gracile in the Fish Removal Lake behaviorally adapted to the presence of introduced fish and were able to recover from the affects of the fish following fish removal. This study underscores the important relationship between species life history and the variability of responses of montane aquatic-breeding amphibians to fish introductions in mountain lakes.

  18. Bacteria and Turbidity Survey for Blue Mountain Lake, Arkansas, Spring and Summer, 1994

    USGS Publications Warehouse

    Lasker, A. Dwight

    1995-01-01

    Introduction Blue Mountain Lake darn is located at river mile 74.4 on the Petit Jean River in Logan and Yell Counties in west-central Arkansas (fig. 1). Drainage area above the darn is 488 square miles. Blue Mountain Lake is located between two national forests-the Ozark National Forest and the Ouachita National Forest. The primary purpose for Blue Mountain Lake is flood control, but the lake is used for a variety of recreational purposes. The U.S. Geological Survey (USGS) in cooperation with the U.s. Army Corps of Engineers, Little Rock District, conducted a bacterial and turbidity study of the Blue Mountain Lake Basin during the spring and suri1mer 1994. Samples were collected weekly at 11 locations within the lake basin from May through September 1994. Eight sampling sites were located on tributaries to the lake and three sampling sites were located on the lake with one of the sites located at a swim beach (fig. 2; table 1).

  19. Toxicity assessment of polycyclic aromatic hydrocarbons in sediments from European high mountain lakes.

    PubMed

    Quiroz, Roberto; Grimalt, Joan O; Fernández, Pilar

    2010-05-01

    Sediment quality guidelines and toxic equivalent factors have been used for assessment of the toxicity of sedimentary long-range atmospherically transported polycyclic aromatic hydrocarbons (PAHs) to the organisms living in high mountain European lakes. This method has provided indices that are consistent with experimental studies evaluating in situ sedimentary estrogenic activity or physiological response to AhR binding in fish from the same lakes. All examined lakes in north, central, west, northeast and southeast European mountains have shown sedimentary PAH concentrations that are above thresholds of no effect but only those situated in the southeast lakes district exhibited concentrations above the indices of probable effects. These mountains, Tatras, are also those having PAH concentrations of highest activity for AhR binding. Chrysene+triphenylene, dibenz[a]anthracene, benzo[k]fluoranthene and indeno[1,2,3-cd]pyrene are the main compounds responsible for the observed toxic effects.

  20. Mountain lakes of Russian subarctic as markers of air pollution: Acidification, metals and paleoecology

    SciTech Connect

    Moiseenko, T.I.; Dauvalter, V.A.; Kagan, L.Y.

    1996-12-31

    The Kola Peninsula mountain lakes reflect a real situation not only of the local air pollution but also polluted transborder emissions from Europe to Arctic and they are of interest for early detection and monitoring for acidification and pollution by heavy metals. Two monitoring mountain lakes had a discrepancy by their resistance to acidification: the Chuna lake is vulnerable and the Chibiny one is not, respectively. Despite the Chuna and Chibiny lakes are close tone of the main heavy metal pollution sources of the Kola Peninsula - smelters of the Severonickel Company, local emissions very slightly affect the mountain lakes, because heavily polluted air masses do not rise in altitude. Sulfur deposition on the Chuna lake catchment is 0.4 gSm{sup -2}, Chibiny lake is 0.6 gSm{sup -2}. In comparison with area at the foot of the mountain (less than 200 m above the sea level) sulfur deposition is 1.0-1.5 gSm{sup -2}. Water quality, sediment chemistry, and diatoms in sediment cores were studied.

  1. Microbial eukaryote plankton communities of high-mountain lakes from three continents exhibit strong biogeographic patterns.

    PubMed

    Filker, Sabine; Sommaruga, Ruben; Vila, Irma; Stoeck, Thorsten

    2016-05-01

    Microbial eukaryotes hold a key role in aquatic ecosystem functioning. Yet, their diversity in freshwater lakes, particularly in high-mountain lakes, is relatively unknown compared with the marine environment. Low nutrient availability, low water temperature and high ultraviolet radiation make most high-mountain lakes extremely challenging habitats for life and require specific molecular and physiological adaptations. We therefore expected that these ecosystems support a plankton diversity that differs notably from other freshwater lakes. In addition, we hypothesized that the communities under study exhibit geographic structuring. Our rationale was that geographic dispersal of small-sized eukaryotes in high-mountain lakes over continental distances seems difficult. We analysed hypervariable V4 fragments of the SSU rRNA gene to compare the genetic microbial eukaryote diversity in high-mountain lakes located in the European Alps, the Chilean Altiplano and the Ethiopian Bale Mountains. Microbial eukaryotes were not globally distributed corroborating patterns found for bacteria, multicellular animals and plants. Instead, the plankton community composition emerged as a highly specific fingerprint of a geographic region even on higher taxonomic levels. The intraregional heterogeneity of the investigated lakes was mirrored in shifts in microbial eukaryote community structure, which, however, was much less pronounced compared with interregional beta-diversity. Statistical analyses revealed that on a regional scale, environmental factors are strong predictors for plankton community structures in high-mountain lakes. While on long-distance scales (>10 000 km), isolation by distance is the most plausible scenario, on intermediate scales (up to 6000 km), both contemporary environmental factors and historical contingencies interact to shift plankton community structures.

  2. Discontinuities in stream nutrient uptake below lakes in mountain drainage networks

    USGS Publications Warehouse

    Arp, C.D.; Baker, M.A.

    2007-01-01

    In many watersheds, lakes and streams are hydrologically linked in spatial patterns that influence material transport and retention. We hypothesized that lakes affect stream nutrient cycling via modifications to stream hydrogeomorphology, source-waters, and biological communities. We tested this hypothesis in a lake district of the Sawtooth Mountains, Idaho. Uptake of NO3- and PO4-3 was compared among 25 reaches representing the following landscape positions: lake inlets and outlets, reaches >1-km downstream from lakes, and reference reaches with no nearby lakes. We quantified landscape-scale hydrographic and reach-scale hydrogeomorphic, source-water, and biological variables to characterize these landscape positions and analyze relationships to nutrient uptake. Nitrate uptake was undetectable at most lake outlets, whereas PO4-3 uptake was higher at outlets as compared to reference and lake inlet reaches. Patterns in nutrient demand farther downstream were similar to lake outlets with a gradual shift toward reference-reach functionality. Nitrate uptake was most correlated to sediment mobility and channel morphology, whereas PO 4-3 uptake was most correlated to source-water characteristics. The best integrated predictor of these patterns in nutrient demand was % contributing area (the proportion of watershed area not routing through a lake). We estimate that NO3- and PO 4-3 demand returned to 50% of pre-lake conditions within 1-4-km downstream of a small headwater lake and resetting of nutrient demand was slower downstream of a larger lake set lower in a watershed. Full resetting of these nutrient cycling processes was not reached within 20-km downstream, indicating that lakes can alter stream ecosystem functioning at large spatial scales throughout mountain watersheds. ?? 2007, by the American Society of Limnology and Oceanography, Inc.

  3. Spatial distribution and temporal development of high-mountain lakes in western Austria

    NASA Astrophysics Data System (ADS)

    Merkl, Sarah; Emmer, Adam; Mergili, Martin

    2015-04-01

    Glacierized high-mountain environments are characterized by active morphodynamics, favouring the rapid appearance and disappearance of lakes. On the one hand, such lakes indicate high-mountain environmental changes such as the retreat of glaciers. On the other hand, they are sometimes susceptible to sudden drainage, leading to glacial lake outburst floods (GLOFs) putting the downstream population at risk. Whilst high-mountain lakes have been intensively studied in the Himalayas, the Pamir, the Andes or the Western Alps, this is not the case for the Eastern Alps. A particular research gap, which is attacked with the present work, concerns the western part of Austria. We consider a study area of approx. 6,140 km², covering the central Alps over most of the province of Tyrol and part of the province of Salzburg. All lakes ≥250 m² located higher than 2000 m asl are mapped from high-resolution Google Earth imagery and orthophotos. The lakes are organized into seven classes: (i) ice-dammed; near-glacial (ii) moraine-dammed and (iii) bedrock-dammed; (iv) moraine-dammed and (v) bedrock-dammed distant to the recent glaciers; (vi) landslide-dammed; (vii) anthropogenic. The temporal development of selected lakes is investigated in detail, using aerial photographs dating back to the 1950s. 1045 lakes are identified in the study area. Only eight lakes are ice-dammed (i). One third of all lakes is located in the immediate vicinity of recent glacier tongues, half of them impounded by moraine (ii), half of them by bedrock (iii). Two thirds of all lakes are impounded by features (either moraines or bedrock) shaped by LIA or Pleistocenic glaciers at some distance to the present glacier tongues (iv and v). Only one landslide-dammed lake (vi) is identified in the study area, whilst 21 lakes are of anthropogenic origin (vii). 72% of all lakes are found at 2250-2750 m asl whilst less than 2% are found above 3000 m asl. The ratio of rock-dammed lakes increases with increasing

  4. A Clean Adirondack (3-D)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is a 3-D anaglyph showing a microscopic image taken of an area measuring 3 centimeters (1.2 inches) across on the rock called Adirondack. The image was taken at Gusev Crater on the 33rd day of the Mars Exploration Rover Spirit's journey (Feb. 5, 2004), after the rover used its rock abrasion tool brush to clean the surface of the rock. Dust, which was pushed off to the side during cleaning, can still be seen to the left and in low areas of the rock.

  5. Monitoring and assessment of anthropogenic activities in mountain lakes: a case of the Fifth Triglav Lake in the Julian Alps.

    PubMed

    Ravnikar, Tina; Bohanec, Marko; Muri, Gregor

    2016-04-01

    The Fifth Triglav Lake is a remote mountain lake in the Julian Alps. The area of the Julian Alps where the lake is situated is protected by law and lies within the Triglav National Park. Mountain lakes in Slovenia were considered for a long time as pristine, unpolluted lakes, but analyses in the last decade revealed considerable human impact even in such remote places. Eutrophication or excessive accumulation of nutrients is the main problem of most lakes in the temperate climatic zone, also in Slovenia. Since the introduction of fish in 1991, the lake is going through a series of changes for which we do not know exactly where they lead, so the monitoring and assessment of anthropogenic activities are of great importance. For this purpose, a qualitative multiattribute decision model was developed with DEX method to assess ecological effects on the lake. The extent of the ecological effects on the lake is assessed using four main parameters: the trophic state, lake characteristics, environmental parameters, and anthropogenic stressors. Dependence of environmental impact on various external factors beyond human control, such as temperature, precipitation, retention time, and factors on which we have influence, such as the amount of wastewater and the presence of fish in the lake, were also evaluated. The following data were measured: chlorophyll a, nutrients, TP, oxygen, C/N ratio, nutrients in sediment, temperature, precipitation, retention time, and volume. We made assumptions about fish and wastewater, which we could not measure. The main contributions of this work are the designed model and the obtained findings for the Fifth Triglav Lake that can help not only scientists in understanding the complexity of lake-watershed systems and interactions among system components but also local authorities to manage and monitor the lake aquatic environment in an effective and efficient way. The model is flexible and can be also used for other lakes, assuming that the used

  6. Hydrological Balance of High Mountainous Lake on Karstified Plateau of Julian Alps - Slovenia

    NASA Astrophysics Data System (ADS)

    Rman, N.; Ratej, J.; Brenčič, M.

    2009-04-01

    High mountainous lake Jezero na Planini pri Jezeru is located in the Triglav National Park at the Julian Alps in Slovenia. It fills a depression covered with Pleistocene fine-grained sediments and glacial till on intensively karstified plateau. In the past many investigations were performed on the lake and its surrounding without knowledge about hydrological balance. The goal of the present study is to fill this gap. Hydrological water balance model of the discussed area was constructed based on results of hydrogeological mapping, soil analyses, infiltration capacity measurements with unsaturated hydraulic parameter analyses, and hydrological modelling. Modelling for soil water balance in the lake catchment area was done with analytical computer program Visual HELP. Free-water-surface evaporation and lake storage calculations were based on other analytical models. A number of different scenarios of possible catchment areas were studied in order to describe the amount of water circulation in the open system of the lake. Scenario that implies that the catchment area is bounded to the nearest vicinity of the lake was proved to be the most realistic. Using the water balance, the paper shows that mountainous lake formed on small accumulation of low permeable sediments on highly permeable and karstified limestone can be self-efficient as precipitation on the lake surface and, moreover, surface runoff from the nearest slopes are sufficient to sustain its volume.

  7. Wolf restoration to the Adirondacks: the advantages and disadvantages of public participation in the decision

    USGS Publications Warehouse

    Mech, L. David; Sharpe, V.A.; Norton, B.; Donnelley, S.

    2000-01-01

    The first time I ever saw a wolf in New York State's Adirondack Mountains was in 1956. It was a brush wolf, or coyote (Canis latrans), not a real wolf, but to an eager young wildlife student this distinction meant little. The presence of this large deer-killing canid let my fresh imagination view the Adirondacks as a real northern wilderness. Since then I have spent the last 40 years studying the real wolf: the gray wolf (Canis lupus). Although inhabiting nearby Quebec and Ontario, the gray wolf still has not made its way back to the Adirondacks as it has to Wisconsin, Michigan, and Montana. Those three states had the critical advantages of a nearby reservoir population of wolves and wilderness corridors through which dispersers from the reservoirs could immigrate. The Adirondacks, on the other hand, are geographically more similar to the greater Yellowstone area in that they are separated from any wolf reservoir by long distances and intensively human-developed areas aversive to wolves from the reservoir populations. If wolves are to return to the Adirondacks, they almost certainly will have to be reintroduced, as they were to Yellowstone National Park. Wolf reintroduction, as distinct from natural recovery, is an especially contentious issue, for it entails dramatic, deliberate action that must be open to public scrutiny, thorough discussion and review, and highly polarized debate. This is as it should be because once a wolf population is reintroduced to an area, it must be managed forever. There is no turning back. The wolf was once eradicated not just from the Adirondacks but from almost all of the 48 contiguous states. That feat was accomplished by a primarily pioneering society that applied itself endlessly to the task, armed with poison. We can never return to those days, so once the wolf is reintroduced successfully, it will almost certainly be here to stay.

  8. Adirondack tourism: perceived consequences of acid rain

    SciTech Connect

    Metz, W.C.

    1984-03-01

    This report seeks to place in perspective the perceived effects of acid precipitation on the tourist industry in the Adirondacks. The 9375-square mile park is host to almost nine million tourists annually, not including seasonal residents. Since the park was established almost 100 years ago, there have been many changes in tourist characteristics, available recreational facilities, kinds of activities, accessibility of the area, and land use and resource management policies. The tourist industry has been influenced by both controllable and uncontrollable factors. At present the overwhelming majority of recreational opportunities and natural resources important to the Adirondack tourist industry are relatively unaffected by acid precipitation. Fishing, a significant component of the tourist industry, is the most vulnerable, but any presumed adverse economic effect has to be weighed against the location of the impacted waters, total Adirondack fishing habitat, substitution available, habitat usage, fisherman characteristics, resource management, and the declining importance of fishing as an Adirondack recreational attraction. Concern is expressed as to whether present minimal acidification impacts are the precursor of major future impacts on Adirondack terrestrial and aquatic environments, and ultimately tourism. Tourism in the Adirondacks is increasing, while many other regional employment sectors are declining. It is becoming a more stable multiseason industry. Its future growth and character will be affected by government, private organization, business community, and resident controversies regarding land use and resource management attitudes, policies, budgets, and regulations. The acid precipitation issue is only one of many related controversies. 65 references, 2 figures.

  9. A hotspot for cold crenarchaeota in the neuston of high mountain lakes.

    PubMed

    Auguet, Jean-Christophe; Casamayor, Emilio O

    2008-04-01

    We have surveyed the first 1 m of 10 oligotrophic high mountain lakes in the Central Pyrenees (Spain) for both abundance and predominant phylotypes richness of the archaeaplankton assemblage, using CARD-FISH and 16S rRNA gene sequencing respectively. Archaea inhabiting the air-water surface microlayer (neuston) ranged between 3% and 37% of total 4,6-diamidino-2-phenylindole (DAPI) counts and were mainly Crenarchaeota of a new freshwater cluster distantly related to the Marine Group 1.1a. Conversely, most of the Archaea from the underlying waters (the remaining first 1 m integrated) were mainly Euryarchaeota of three distantly related branches ranging between 0.4% and 27% of total DAPI counts. Therefore, a consistent qualitative and quantitative spatial segregation was observed for the two main archaeal phyla between neuston and underlying waters at a regional scale. We also observed a consistent pattern along the lakes surveyed between lake area, lake depth and water residence time, and the archaeal enrichment in the neuston: the larger the lake the higher the proportion of archaea in the neuston as compared with abundances from the underlying waters (n = 10 lakes; R(2) > 0.80; P < 0.001, in all three cases). This is the first report identifying a widespread non-thermophilic habitat where freshwater planktonic Crenarchaeota can be found naturally enriched. High mountain lakes offer great research opportunities to explore the ecology of one of the most enigmatic and far from being understood group of prokaryotes.

  10. How climate changes in the Rocky Mountains contribute to changes in an alpine lake's phytoplankton community

    NASA Astrophysics Data System (ADS)

    Guido, A. S.; Garland, D.; McKnight, D. M.

    2011-12-01

    It is important to track algae in potable water supplies as they are a factor in the production of dissolved organic matter (DOM) that can result in the formation of disinfection byproducts. Disinfection byproducts have been identified by the Environmental Protection Agency (EPA) as a potential carcinogen and have been linked to reproductive and developmental effects in lab animals. Green Lake 4 is located in the Rocky Mountains and is part of the Silver Lake Watershed which provides 40% of Boulder, CO's potable water supply. In 2002, the Rocky Mountain region had below average precipitation and consequently Green Lake experienced a change in its physical and chemical conditions. As a result of the changes experienced in Green Lake 4, a change in the composition of the phytoplankton community was seen. Along with reduced precipitation levels, this area has also experienced an earlier ice-out date. As part of this research, chemical changes, physical changes, and algae changes in Green Lake 4 will be analyzed. Data from 2007 to 2010 will be analyzed; this study will be looking at both the chemical and physical changes of Green Lake 4 as they relate to the change in ice out of the lake and precipitation in the region.

  11. ESTIMATION OF SURPLUS BIOMASS OF CLUPEIDS IN SMITH MOUNTAIN LAKE, VIRGINIA

    EPA Science Inventory

    Mean annual estimates of surplus biomass of alewife Alosa pseudoharengus and gizzard shad Dorosoma cepedianum in Smith Mountain Lake, Virginia, were calculated using data on the biomass, growth, and mortality of each clupeid species. Surplus biomass, defined as production over a...

  12. [Limnology of high mountain tropical lake, in Ecuador: characteristics of sediments and rate of sedimentation].

    PubMed

    Gunkel, Günter

    2003-06-01

    Equatorial high mountain lakes are a special type of lake occurring mainly in the South American Andes as well as in Central Africa and Asia. They occur at altitudes of a few thousand meters above sea level and are cold-water lakes (< 20 degrees C). Relatively little is known about them. A long-term limnological study was therefore undertaken at Lake San Pablo, Ecuador, to analyze the basic limnological processes of the lake, which has a tendency for eutrophication. Sediment quality of San Pablo Lake is given under consideration of horizontal and vertical distribution using sediment cores. Significance of sediments for eutrophication process of lakes is demonstrated using phosphorus concentration of sediments as well as the phosphorus retention capacity of the sediments by ratio Fe/P. Dating of the sediments is done using 137Cs and 210Pb, but the activity of 137Cs in the sediment was very low nearly at the detection level. Sedimentation rate is determined to be 3.5 mm/year and the sediment cores represent about 110 years. P concentration of the sediments is high (approximately 5 g/kg dry substance), and P retention capacity by Fe is insufficient (Fe/P = 4). The sediment quality did not change significantly during the past decades, and the trophic state of San Pablo Lake was already less or more eutrophic 110 years ago. The contamination of the lake sediments by heavy metals is insignificant.

  13. Sediment fluxes of polycyclic aromatic hydrocarbons in European high altitude mountain lakes

    SciTech Connect

    Fernandez, P.; Vilanova, R.M.; Grimalt, J.O.

    1999-11-01

    Polycyclic aromatic hydrocarbons (PAH) were measured in superficial sediments from several high altitude mountain lakes for assessment of contemporary background PAH pollution levels in Europe. The sediments were obtained by gravity coring, and the upper 0--1 cm were analyzed by gas chromatography coupled to mass spectrometry. The parent PAH mixtures are very uniform irrespective of lake location, lake characteristics, and PAH load, corresponding to airborne combustion mixtures refractory to photooxidation and chemical degradation. The sedimentary fluxes are lowest in Lake Arresjoeen (Arctic area), 6.9 {micro}g/m{sup 2}yr, between 44 and 150 {micro}g/m{sup 2}yr in west and central Europe and very high, 960--1,700 {micro}g/m{sup 2}yr, in east Europe. Normalization of these values to TOC reflects a uniform pattern in correspondence with continental influence and east-west distribution. This pattern parallels the annual average atmospheric deposition fluxes of sulfate, pointing to combustion particles as the main way of PAH transport into these high altitude lakes. The lowest PAH/TOC ratios are found in the sites more distant from the continent, the westernmost locations constitute another group higher values are found in the Alps and Pyrenees, and the most polluted lakes are found in the Tatra mountains.

  14. Decline of red spruce in the Adirondacks, New York

    SciTech Connect

    Scott, J.T.; Siccama, T.G.; Johnson, A.H.; Breisch, A.R.

    1984-01-01

    Thirty-two stands in the spruce-fir forests of Whiteface Mountain in the Adirondacks, originally sampled from 1964-66, were resurveyed in 1982. From 10-25 Bitterlich points were used in each stand in 1982 to obtain an estimate of basal area per hectare. Data were summarized for low elevation (<900m) and high elevation (> or = 900m) forests. Red spruce declined by 40-60% in basal area for the low elevation forests and by 60-70% above 900m. Balsam fir decreased by 35% at high elevations, due to natural disturbance in several of the stands, but was unchanged when only undisturbed stands were considered. The decline of red spruce accounted for about three quarters of the total decrease in basal area for both the high- and low-elevation forests. Spruce seedling frequency for the high-elevation sample decreased by 80%, but was unchanged below 900m. The pattern of spruce decline in the Adirondacks is similar to findings for New England. The cause of the decline is speculative at the time.

  15. Implications for Ecosystem Services of Watershed Processes that affect the Transport and Transformations of Mercury in an Adirondack Stream Basin

    NASA Astrophysics Data System (ADS)

    Burns, D. A.; Riva-Murray, K.; Bradley, P. M.

    2012-12-01

    Mercury (Hg) is a potent neurotoxin that can affect the health of humans and wildlife through the ingestion of methyl Hg. Mercury contamination of ecosystems originates from human activities such as mining, coal burning and other industrial emissions, and the use of Hg-containing products. Natural sources such as volcanic and geothermal emissions and the weathering of Hg-bearing minerals also contribute to Hg contamination, but are believed to be minor sources in most ecosystems. Various ecosystem disturbances including fires, forest harvesting, and the submergence of land by impoundment may also contribute to Hg ecosystem contamination by mobilizing stores that have previously originated from the sources described above. Mercury from a mix of regional and global emissions sources is transported in the atmosphere to remote landscapes that are distant from local emissions sources. The Adirondacks of New York State is a forested, mountainous region characterized by abundant lakes and streams, and is distant from local emissions sources. Recreational fishing, wildlife viewing, hiking, and hunting are valued ecosystem services in this region. Here, we report on the relevance to ecosystem services of findings based on five years of Hg data collection of stream water, groundwater, invertebrates, and fish in the upper Hudson River basin in the central part of the Adirondack region. The New York State Dept. of Health has issued fish consumption advisories for the entire Adirondacks based on elevated levels previously measured in lakes and rivers of this region. Our work seeks improved understanding and models of the landscape sources and watershed processes that control the transformation of Hg to its methyl form (MeHg), the transport of MeHg to streams, and bioaccumulation of MeHg in aquatic food webs. Mean annual atmospheric Hg deposition was 6.3 μg/m2/yr during 2007-09, compared to mean annual filtered total Hg stream yields of 1.66 μg/m2/yr and filtered MeHg stream

  16. Diatom Community Changes in Five Sub-alpine Mountain Lakes in Northern California

    NASA Astrophysics Data System (ADS)

    Johnson, B.; Noble, P. J.; Howard, K.; Heyvaert, A.

    2012-12-01

    Sediment cores and/or phytoplankton sampling of five sub-alpine lakes within three northern California mountain ranges show a major shift in diatom phytoplankton communities over the past 20-60 years; however, specific causes of these changes are still under investigation. Diatom analysis of a 20-cm sediment core taken from Castle Lake, a meso-oligotrophic lake located on the eastern slope of the Klammath Mountains, shows the phytoplankton community shifted from being cyclotelloid-dominated to having a larger component of araphids beginning around 1997. In the lower 14 cm of the core, the phytoplankton are dominated by centric diatoms, including the Discostella stelligera-pseudostelligera group (>50% of total diatoms), and the Cyclotella occelata-rossii-tripartita complex (9-18%). The top 6 cm show an increasing shift towards araphids, including Asterionella formosa and the Fragilaria tenera-nanana group, which is consistent with phytoplankton in the lake's epilimnion today. Fallen Leaf Lake (FLL), located at the southern end of the Lake Tahoe basin, has also undergone a similar shift. Presently, A. formosa, the F. tenera-nananna group, and Tabellaria dominate the phytoplankton. Examination of a sediment core from FLL indicates that A. formosa has been present in high abundances since at least 1812. The most prominent shift in the FLL diatom population began in the 1950s when the centric diatoms (eg. Aulacoseira subarctica) declined significantly in favor of araphids. The F. tenera-nanana group was present in trace amounts before 1812 and dramatically increased in abundance after the 1950s. Sediment accumulation rates have increased steadily since 1950 and coincide with increases in lake development and recreational use. A. formosa is also present today in Gilmore Lake, a minimally human-impacted lake located in the watershed above FLL, and in the heavily impacted Manzanita Lake in the northwestern corner of Lassen Volcanic National Park (LAVO) at the southern end

  17. Metagenomics Reveals a Novel Virophage Population in a Tibetan Mountain Lake.

    PubMed

    Oh, Seungdae; Yoo, Dongwan; Liu, Wen-Tso

    2016-06-25

    Virophages are parasites of giant viruses that infect eukaryotic organisms and may affect the ecology of inland water ecosystems. Despite the potential ecological impact, limited information is available on the distribution, diversity, and hosts of virophages in ecosystems. Metagenomics revealed that virophages were widely distributed in inland waters with various environmental characteristics including salinity and nutrient availability. A novel virophage population was overrepresented in a planktonic microbial community of the Tibetan mountain lake, Lake Qinghai. Our study identified coccolithophores and coccolithovirus-like phycodnaviruses in the same community, which may serve as eukaryotic and viral hosts of the virophage population, respectively.

  18. Metagenomics Reveals a Novel Virophage Population in a Tibetan Mountain Lake

    PubMed Central

    Oh, Seungdae; Yoo, Dongwan; Liu, Wen-Tso

    2016-01-01

    Virophages are parasites of giant viruses that infect eukaryotic organisms and may affect the ecology of inland water ecosystems. Despite the potential ecological impact, limited information is available on the distribution, diversity, and hosts of virophages in ecosystems. Metagenomics revealed that virophages were widely distributed in inland waters with various environmental characteristics including salinity and nutrient availability. A novel virophage population was overrepresented in a planktonic microbial community of the Tibetan mountain lake, Lake Qinghai. Our study identified coccolithophores and coccolithovirus-like phycodnaviruses in the same community, which may serve as eukaryotic and viral hosts of the virophage population, respectively. PMID:27151658

  19. Oxygen isotope evidence for shallow emplacement of Adirondack anorthosite

    USGS Publications Warehouse

    Valley, J.W.; O'Neil, J.R.

    1982-01-01

    Oxygen isotopic analysis of wollastonites from the Willsboro Mine, Adirondack Mountains, New York reveals a 400-ft wide zone of 18O depletion at anorthosite contacts. Values of ??18O vary more sharply with distance and are lower (to -1.3) than any yet reported for a granulite fades terrain. Exchange with circulating hot meteoric water best explains these results and implies that the anorthosite was emplaced at relatively shallow depths, <10 km, in marked contrast to the depth of granulite fades metamorphism (23 km). These 18O depletions offer the first strong evidence for shallow emplacement of anorthosite within the Grenville Province and suggest that regional metamorphism was a later and tectonically distinct event. ?? 1982 Nature Publishing Group.

  20. Chemical data for bottom sediment, lake water, bottom-sediment pore water, and fish in Mountain Creek Lake, Dallas, Texas, 1994-96

    USGS Publications Warehouse

    Jones, S.A.; Van Metre, P.C.; Moring, J.B.; Braun, C.L.; Wilson, J.T.; Mahler, B.J.

    1997-01-01

    Mountain Creek Lake is a reservoir adjacent to two U.S. Department of the Navy facilities, the Naval Weapons Industrial Reserve Plant and the Naval Air Station in Dallas, Texas. A Resource Conservation and Recovery Act Facility Investigation found ground-water plumes containing chlorinated solvents on both facilities. These findings led to a U.S. Geological Survey study of Mountain Creek Lake adjacent to both facilities between June 1994 and August 1996. Bottom sediments, lake water, bottom-sediment pore water, and fish were collected for chemical analysis.

  1. Three new Psammothidium species from lakes of Olympic and Cascade Mountains in Washington State, USA

    USGS Publications Warehouse

    Enache, Mihaela D.; Potapova, Marina; Sheibley, Rich; Moran, Patrick

    2013-01-01

    Populations of several Psammothidium species were found in core sediments from nine remote, high elevation, ultraoligotrophic and oligotrophic, Olympic and Cascade Mountain lakes. Three of these species, P. lacustre, P. alpinum, and P. nivale, are described here as new. The morphology of the silica frustules of these species was documented using light and scanning electron microscopy. We discuss the similarities and differences with previously described Psammothidium species.

  2. Geohydrologic reconnaissance of Lake Mead National Recreation Area; Las Vegas Wash to Opal Mountain, Nevada

    USGS Publications Warehouse

    Laney, R.L.

    1981-01-01

    The study is a geohydrologic reconnaissance of about 170 square miles in the Lake Mead National Recreation Area from Las Vegas Wash to Opal Mountain, Nevada. The study is one of a series that describes the geohydrology of the recreation area and that indentifies areas where water supplies can be developed. Precipitation in this arid area is about 5 inches per year. Streamflow is seasonal and extremely variable except for that in the Colorado River, which adjoins the area. Pan evaporation is more than 20 times greater than precipitation; therefore, regional ground-water supplies are meager except near the Colorado River, Lake Mead, and Lake Mohave. Large ground-water supplies can be developed near the river and lakes, and much smaller supplies may be obtained in a few favorable locations farther from the river and lakes. Ground water in most of the areas probably contains more than 1,000 milligrams per liter of dissolved solids, but water that contains less than 1,000 milligrams per liter of dissolved solids can be obtained within about 1 mile of the lakes. Crystalline rocks of metamorphic, intrusive and volcanic origin crop out in the area. These rocks are overlain by conglomerate and mudstone of the Muddy Creek Formation, gravel and conglomerate of the older alluvium, and sand and gravel of the Chemehuevi Formation and younger alluvium. The crystalline rocks, where sufficiently fractured, yield water to springs and would yield small amounts of water to favorably located wells. The poorly cemented and more permeable beds of the older alluvium, Chemehuevi Formation, and younger alluvium are the better potential aquifers, particularly along the Colorado River and Lakes Mead and Mohave. Thermal springs in the gorge of the Colorado River south of Hoover Dam discharge at least 2,580 acre-feet per year of water from the volcanic rocks and metamorphic and plutonic rocks. The discharge is much greater than could be infiltrated in the drainage basin above the springs

  3. The relative influences of climate and volcanic activity on Holocene lake development inferred from a mountain lake in central Kamchatka

    NASA Astrophysics Data System (ADS)

    Self, A. E.; Klimaschewski, A.; Solovieva, N.; Jones, V. J.; Andrén, E.; Andreev, A. A.; Hammarlund, D.; Brooks, S. J.

    2015-11-01

    A sediment sequence was taken from a closed, high altitude lake (informal name Olive-backed Lake) in the central mountain range of Kamchatka, in the Russian Far East. The sequence was dated by radiocarbon and tephrochronology and used for multi-proxy analyses (chironomids, pollen, diatoms). Although the evolution of Beringian climate through the Holocene is primarily driven by global forcing mechanisms, regional controls, such as volcanic activity or vegetation dynamics, lead to a spatial heterogeneous response. This study aims to reconstruct past changes in the aquatic and terrestrial ecosystems and to separate the climate-driven response from a response to regional or localised environmental change. Radiocarbon dates from plant macrophytes gave a basal date of 7800 cal yr BP. Coring terminated in a tephra layer, so sedimentation at the lake started prior to this date, possibly in the early Holocene following local glacier retreat. Initially the catchment vegetation was dominated by Betula and Alnus woodland with a mosaic of open, wet, aquatic and semi-aquatic habitats. Between 7800 and 6000 cal yr BP the diatom-inferred lake water was pH 4.4-5.3 and chironomid and diatom assemblages in the lake were initially dominated by a small number of acidophilic/acid tolerant taxa. The frequency of Pinus pumila (Siberian dwarf pine) pollen increased from 5000 cal yr BP and threshold analysis indicates that P. pumila arrived in the catchment between 4200 and 3000 cal yr BP. Its range expansion was probably mediated by strengthening of the Aleutian Low pressure system and increased winter snowfall. The diatom-inferred pH reconstructions show that after an initial period of low pH, pH gradually increased from 5500 cal yr BP to pH 5.8 at 1500 cal yr BP. This trend of increasing pH through the Holocene is unusual in lake records, but the initially low pH may have resulted directly or indirectly from intense regional volcanic activity during the mid-Holocene. The chironomid

  4. Comparison of 15 evaporation methods applied to a small mountain lake in the northeastern USA

    USGS Publications Warehouse

    Rosenberry, D.O.; Winter, T.C.; Buso, D.C.; Likens, G.E.

    2007-01-01

    Few detailed evaporation studies exist for small lakes or reservoirs in mountainous settings. A detailed evaporation study was conducted at Mirror Lake, a 0.15 km2 lake in New Hampshire, northeastern USA, as part of a long-term investigation of lake hydrology. Evaporation was determined using 14 alternate evaporation methods during six open-water seasons and compared with values from the Bowen-ratio energy-budget (BREB) method, considered the standard. Values from the Priestley-Taylor, deBruin-Keijman, and Penman methods compared most favorably with BREB-determined values. Differences from BREB values averaged 0.19, 0.27, and 0.20 mm d-1, respectively, and results were within 20% of BREB values during more than 90% of the 37 monthly comparison periods. All three methods require measurement of net radiation, air temperature, change in heat stored in the lake, and vapor pressure, making them relatively data intensive. Several of the methods had substantial bias when compared with BREB values and were subsequently modified to eliminate bias. Methods that rely only on measurement of air temperature, or air temperature and solar radiation, were relatively cost-effective options for measuring evaporation at this small New England lake, outperforming some methods that require measurement of a greater number of variables. It is likely that the atmosphere above Mirror Lake was affected by occasional formation of separation eddies on the lee side of nearby high terrain, although those influences do not appear to be significant to measured evaporation from the lake when averaged over monthly periods. ?? 2007 Elsevier B.V. All rights reserved.

  5. Sediment Characteristics of a High-Mountain Lake in South Central Anatolia, Turkey

    NASA Astrophysics Data System (ADS)

    Ataselim, Zeynep; Leroy, Suzanne; Gurbuz, Alper; Gurbuz, Esra; Onur Yucel, Tahsin; Yedek, Ozgur; Koc, Koray

    2016-04-01

    Lake Dipsiz is at the top of Mount Erenler, located 55 km west of Konya city in Central Anatolia, Turkey. Mount Erenler is the largest part of Central Anatolia Volcanic Province and consists of Miocene-Pliocene calc-alkaline lavas together with pyroclastic rocks and covers an area approximately 2000 km2. The peak of the Mount Erenler is at 1900 m while Lake Dipsiz is located at 1600 m altitude. Despite the small surface area (0.33 km2), the depth is relatively high (16 m). The drainage area of the lake is 8 km2. Although the topography of the lake points out to glacier presence, it formed as a landslide-dammed lake. Lake Dipsiz geographically is between mountainous Mediterranean region and Central Anatolia plateau. Climatically, the lake is in a transition zone between Taurids and Central Anatolia. In this study, we investigated sedimentation in a high altitude lake at a climatic transition. For this purpose, three cores (D1, D2 and D3) which are 50 cm length are taken with a hand corer from the coastline of the lake. D1 and D2 cores are sampled in every 2 cm and D3 core is samples in every 1 cm. Geochemical, total organic carbon, magnetic susceptibility and total carbonate analyses were performed on all sample sets. Lake sediments are brownish/green clay and silt in composition. Despite the proximity of the sediment source, no sand or more coarse grains were observed in the sedimentary filling. Organic matter content is between 2 - 28 %. According to one 14C date, the sequence indicates a Late Holocene age. δ13C isotope values are between -28.9 and -25.3 ‰ and it means that the sediment composed of terrestrial C3 organic matter. The detrital input in the lake has increased in the last 1000 years. Sedimentation rate was low between 3000 and cal. 1700 BP to the contrary of significant increasing from 250 BP to nowadays. Our data show that the sedimentation in this high altitude lake is more sensitive to other environmental conditions rather than climate.

  6. Biogeochemical and microbial seasonal dynamics between water column and sediment processes in a productive mountain lake: Georgetown Lake, MT, USA

    NASA Astrophysics Data System (ADS)

    Parker, Stephen R.; West, Robert F.; Boyd, Eric S.; Feyhl-Buska, Jayme; Gammons, Christopher H.; Johnston, Tyler B.; Williams, George P.; Poulson, Simon R.

    2016-08-01

    This manuscript details investigations of a productive, mountain freshwater lake and examines the dynamic relationship between the chemical and stable isotopes and microbial composition of lake bed sediments with the geochemistry of the lake water column. A multidisciplinary approach was used in order to better understand the lake water-sediment interactions including quantification and sequencing of microbial 16S rRNA genes in a sediment core as well as stable isotope analysis of C, S, and N. One visit included the use of a pore water sampler to gain insight into the composition of dissolved solutes within the sediment matrix. Sediment cores showed a general decrease in total C with depth which included a decrease in the fraction of organic C combined with an increase in the fraction of inorganic C. One sediment core showed a maximum concentration of dissolved organic C, dissolved inorganic C, and dissolved methane in pore water at 4 cm depth which corresponded with a sharp increase in the abundance of 16S rRNA templates as a proxy for the microbial population size as well as the peak abundance of a sequence affiliated with a putative methanotroph. The isotopic separation between dissolved inorganic and dissolved organic carbon is consistent with largely aerobic microbial processes dominating the upper water column, while anaerobic microbial activity dominates the sediment bed. Using sediment core carbon concentrations, predictions were made regarding the breakdown and return of stored carbon per year from this temperate climate lake with as much as 1.3 Gg C yr-1 being released in the form of CO2 and CH4.

  7. Disruptions of stream sediment size and stability by lakes in mountain watersheds: Potential effects on periphyton biomass

    USGS Publications Warehouse

    Myers, A.K.; Marcarelli, A.M.; Arp, C.D.; Baker, M.A.; Wurtsbaugh, W.A.

    2007-01-01

    The location of a stream reach relative to other landforms in a watershed is an important attribute. We hypothesized that lakes disrupt the frequency of finer, more mobile sediments and thereby change sediment transport processes such that benthic substrates are more stable (i.e., less mobile) below lakes than above lakes. In turn, we hypothesized that this reduced mobility would lead to greater periphyton biomass below lakes. We tested these hypotheses in study reaches above and below lakes in 3 mountain watersheds. To expand this comparison, we analyzed the relationship between sediment attributes and periphyton biomass in one watershed with and one watershed without a lake. We hypothesized that no clear pattern or change in sediment size or chlorophyll a (chl a) would be observed over a 3-km-long study reach without a lake. In contrast, we expected a clear discontinuity in both sediment size and chl a in a 7-km-long study reach interrupted by a lake. Average median sediment size (D50) was significantly larger (p < 0.01) in lake-outlet than lake-inlet reaches (41 mm vs 10 mm). Bed sediments in lake-outlet reaches were immobile during bankfull flows, whereas sediments at lake-inlet reaches were mobile during bankfull flows. Chlorophyll a was ???10x greater in lake-outlet reaches than in lake-inlet reaches, although this difference was not statistically significant (p = 0.17). The longitudinal analysis clearly showed geomorphic transitions in sediment size and mobility downstream of mountain lakes, and these geomorphic transitions might be associated with changes in periphyton biomass. Geomorphic transitions can alter sediment transport and should be considered in concert with other factors that are considered more commonly in benthic ecology, such as light, nutrients, and temperature. ?? 2007 by The North American Benthological Society.

  8. Tracking climate change in oligotrophic mountain lakes: Recent hydrology and productivity synergies in Lago de Sanabria (NW Iberian Peninsula).

    PubMed

    Jambrina-Enríquez, Margarita; Recio, Clemente; Vega, José Carlos; Valero-Garcés, Blas

    2017-07-15

    Mountain lakes are particularly sensitive to global change as their oligotrophic conditions may be rapidly altered after reaching an ecological threshold, due to increasing human impact and climate change. Sanabria Lake, the largest mountain lake in the Iberian Peninsula and with a recent history of increased human impact in its watershed, provides an opportunity to investigate recent trends in an oligotrophic, hydrologically-open mountain lake, and their relationship with climate, hydrological variability and human pressure. We conducted the first systematic and detailed survey of stable isotope compositions of Sanabria Lake and Tera River together with limnological analyses during 2009-2011. δ(18)Olakewater and δDlakewater seasonal fluctuations are strongly linked to river discharges, and follow the monthly mean isotopic composition of precipitation, which is controlled by NAO dynamics. δ(13)CPOM and δ(13)CDIC revealed higher contribution of allochthonous organic matter in winter and spring due to higher river inflow and lower primary productivity. Increased phytoplankton biomass in late summer correlated significantly with higher pH and Chl-a, and higher nutrient input and lower river inflow. However, the small δ(13)CPOM seasonal amplitude underlines the stability of the oligotrophic conditions and the isotopic variation in POM and DIC reflect small seasonal fluctuations mostly as a consequence of strong throughflow. The stability of hydrology and productivity patterns is consistent with Holocene and last millennium reconstructions of past limnological changes in Sanabria Lake. The results of this study indicate that trophic state in this hydrologically-open mountain lake is strongly controlled by climate variability, but recent changes in human-land uses have increased sediment delivery and nutrients supply to the lake and have to be considered for management policies. Monitoring surveys including isotope techniques provide snapshots of modern isotope

  9. High-levels of microplastic pollution in a large, remote, mountain lake.

    PubMed

    Free, Christopher M; Jensen, Olaf P; Mason, Sherri A; Eriksen, Marcus; Williamson, Nicholas J; Boldgiv, Bazartseren

    2014-08-15

    Despite the large and growing literature on microplastics in the ocean, little information exists on microplastics in freshwater systems. This study is the first to evaluate the abundance, distribution, and composition of pelagic microplastic pollution in a large, remote, mountain lake. We quantified pelagic microplastics and shoreline anthropogenic debris in Lake Hovsgol, Mongolia. With an average microplastic density of 20,264 particles km(-2), Lake Hovsgol is more heavily polluted with microplastics than the more developed Lakes Huron and Superior in the Laurentian Great Lakes. Fragments and films were the most abundant microplastic types; no plastic microbeads and few pellets were observed. Household plastics dominated the shoreline debris and were comprised largely of plastic bottles, fishing gear, and bags. Microplastic density decreased with distance from the southwestern shore, the most populated and accessible section of the park, and was distributed by the prevailing winds. These results demonstrate that without proper waste management, low-density populations can heavily pollute freshwater systems with consumer plastics.

  10. Hydrologic and water-quality data from Mountain Island Lake, North Carolina, 1994-97

    USGS Publications Warehouse

    Sarver, K.M.; Steiner, B.C.

    1998-01-01

    Continuous-record water-level gages were established at three sites on Mountain Island Lake and one site downstream from Mountain Island Dam. The water level of Mountain Island Lake is controlled by Duke Power Company releases at Cowans Ford Dam (upstream) and Mountain Island Dam (downstream). Water levels on Mountain Island Lake measured just downstream from Cowans Ford Dam fluctuated 11.15 feet during the study. Water levels just upstream from the Mountain Island Lake forebay fluctuated 6.72 feet during the study. About 3 miles downstream from Mountain Island Dam, water levels fluctuated 5.31 feet. Sampling locations included 14 sites in Mountain Island Lake, plus one downstream river site. At three sites, automated instruments recorded water temperature, dissolved-oxygen concentration, and specific conductance at 15-minute intervals throughout the study. Water temperatures recorded continuously during the study ranged from 4.2 to 35.2 degrees Celsius, and dissolved-oxygen concentrations ranged from 2.1 to 11.8 milligrams per liter. Dissolved-oxygen concentrations generally were inversely related to water temperature, with lowest dissolved-oxygen concentrations typically recorded in the summer. Specific conductance values recorded continuously during the study ranged from 33 to 89 microsiemens per centimeter; however, mean monthly values were fairly consistent throughout the study at all sites (50 to 61 microsiemens per centimeter). In addition, vertical profiles of water temperature, dissolved-oxygen concentration, specific conductance, and pH were measured at all sampling locations during 24 site visits. Water-quality constituent concentrations were determined for seven reservoir sites and the downstream river site during 17 sampling trips. Water-quality samples were routinely analyzed for biochemical oxygen demand, fecal coliform bacteria, hardness, alkalinity, total and volatile suspended solids, nutrients, total organic carbon, chlorophyll, iron, calcium

  11. Quantifying Sediment Delivery History in Mediterranean Mountain Watersheds from Lake Records (Iberian Range, Spain)

    NASA Astrophysics Data System (ADS)

    Valero-Garcés, Blas; Barreiro-Lostres, Fernando; Moreno, Ana; González-Sampériz, Penélope; Giralt, Santiago; Nadal-Romero, Estela

    2016-04-01

    Land degradation and soil erosion are key environmental problems in Mediterranean mountains with long history of human occupation and strong seasonality of hydrological regimes. Monitoring studies in experimental catchments in the Pyrenees have identified main controlling factors on erosion dynamics but, because of the short time span, they do not integrate the diverse temporal and spatial variability of these environments. We propose a novel strategy based on multi-proxy analyses of lake sediments aimed to quantify sediment delivery and erosion dynamics. Karstic lakes in the Iberian Range (Spain) provide the opportunity to reconstruct the depositional evolution of Mediterranean mountain watersheds and to evaluate the response to both, anthropogenic and climate forcings during the last millennia. Precipitation (rainfall intensity, seasonality, runoff production) and land cover (forest area, degraded areas, land uses) are key factors controlling erosion in both experimental and lake catchments. Values for Minimum Denuded Mass (Mdc) and Total Denudation Rate (DRt) measured in experimental catchments and reconstructed from lake sequences are comparable. In both settings, most sediment yield occurs during flooding events. The reconstructed sediment delivery to the lakes during flood events spans several orders or magnitude (less than 100 T to 98000 T) and the denudation rate ranges from 6 to 480 T km-2 yr-1. Reconstructed mass denudation values per event in the forested lake catchments are similar (less than 30 T km-2 yr-1) to sediment yields from a high altitude experimental watershed. Flood sediment yield values from an abandoned farmland experimental catchment (69 T km2) are in the lower range of lake watersheds (from 60 to 480 T km-2 yr-1). No lake watershed has reached the values documented for the badland catchment (3094 T km-2). These results underline the punctuated nature of sediment dynamics in Mediterranean landscapes at decadal and centennial scales. Major

  12. Mountains

    SciTech Connect

    Fuller, M.

    1989-01-01

    This book covers the following topics: Above the forest: the alpine tundra; Solar energy, water, wind and soil in mountains; Mountain weather; Mountain building and plate tectonics; Mountain walls: forming, changing, and disappearing; Living high: mountain ecosystems; Distribution of mountain plants and animals; On foot in the mountains: how to hike and backpack; Ranges and peaks of the world. Map and guidebook sources, natural history and mountain adventure trips, mountain environmental education centers and programs, and sources of information on trails for the handicapped are included.

  13. Benthic plant communities in acidic Lake Colden, New York: Sphagnum and the algal mat

    SciTech Connect

    Hendrey, G R; Vertucci, J A

    1980-03-01

    Lake Colden, in the central Adirondack Mountains of New York State is botanically similar to acidified lakes in Sweden. Acidification of some Swedish lakes has been associated with an expansion of Sphagnum, primarily in shallow, sheltered littoral areas but also to depths of 18m. During a brief botanical survey on 24-25 July 1979, we observed a dense meadow of Sphagnum pylaesii around much of the shoreline of Lake Colden. Plant community composition was determined by a visual estimate of cover along a single typical transect and through underwater photography on 28-29 August 1979. Water samples were collected and returned to our laboratory for analyses several days later. Sample pH was determined by potentiometry and alkalinity by multiple end point titrations. Biomass samples were also taken of the Sphagnum mat community and dry weight was determined. Chemical content of plant tissue was analyzed.

  14. Atmospherc deposition of organochlorine compounds to remote high mountain lakes of Europe.

    PubMed

    Carrera, Guillem; Fernández, Pilar; Grimalt, Joan O; Ventura, Marc; Camarero, Lluis; Catalan, Jordi; Nickus, Ulrike; Thies, Hansjörg; Psenner, Roland

    2002-06-15

    Bulk deposition samples were taken near three mountain lakes located in the Pyrenees (Estany Redó), Alps (Gossenköllesee), and Caledonian Mountains (Ovre Neådalsvatn) for evaluation of the atmospheric deposition load of organochlorine compounds (OC), namely, polychlorobiphenyls (PCBs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), and endosulfans, in the remote European high mountain areas. The compounds of present use in agriculture, namely, endosulfans and gamma-HCH, exhibit large differences in mean deposition fluxes between the three sites. They occur in large amounts in Estany Redó (340 and 430 ng m(-2) month(-1) for endosulfans and gamma-HCH, respectively), reflecting the impact of agricultural activities in southern Europe. This lake showed also the highest proportion of the more labile endosulfan isomers (alpha and beta = 82%) whereas only the most recalcitrant species, endosulfan sulfate, was found in Ovre Neådalsvatn. In contrast, the OC whose use is now banned exhibit a more uniform geographic distribution with deposition fluxes of 31-40, 30-100, and 1.4-15 ng m(-2) month(-1) for alpha-HCH, PCBs, and HCB. Both compounds of present and past use exhibit a clear seasonal pattern, with higher deposition in the warm periods, which is consistent with enhanced volatilization at higher temperatures. In the case of the agricultural pesticides it may also reflect higher use during application periods. The OC distributions in the atmospheric deposition of the three sites are rather uniform and highly enriched in compounds with volatilities larger than 0.0032 Pa. However, more than 90% of these compounds are not retained in the lake waters or sediments. Comparison of OC composition in atmospheric and sedimentary deposition evidences a selective trapping of the less volatile compounds. Trapping efficiencies increase at decreasing air temperatures of the lacustrine systems.

  15. Native Salamanders and Introduced Fish: Changing the Nature of Mountain Lakes and Ponds

    USGS Publications Warehouse

    Larson, Gary L.; Hoffman, Robert L.

    2003-01-01

    During the last century, many fishless mountain lakes and ponds in the Pacific Northwest were stocked with non-native fish, such as brook trout, for recreational purposes. These introduced fish replaced long-toed and northwestern salamander larvae as the top aquatic vertebrate predator by preying on salamander larvae. This predatory interaction has been shown to reduce the abundances of larval salamander populations. We conducted studies in two national parks to assess the abundances of salamander larvae in lakes with and without introduced fish. These studies suggest that the two salamander species were affected quite differently by the presence of introduced fish because of different life-history traits and different distributions of salamanders and fish within each park.

  16. Sampling protocol for monitoring abiotic and biotic characteristics of mountain ponds and lakes

    USGS Publications Warehouse

    Hoffman, Robert L.; Tyler, Torrey J.; Larson, Gary L.; Adams, Michael J.; Wente, Wendy; Galvan, Stephanie

    2005-01-01

    This document describes field techniques and procedures used for sampling mountain ponds and lakes. These techniques and procedures will be used primarily to monitor, as part of long-term programs in National Parks and other protected areas, the abiotic and biotic characteristics of naturally occurring permanent montane lentic systems up to 75 ha in surface area. However, the techniques and procedures described herein also can be used to sample temporary or ephemeral montane lentic sites. Each Standard Operating Procedure (SOP) section addresses a specific component of the limnological investigation, and describes in detail field sampling methods pertaining to parameters to be measured for each component.

  17. Integrating physical and chemical characteristics of lakes into the glacially influenced landscape of the Northern Cascade Mountains, Washington State, USA

    USGS Publications Warehouse

    Larson, Gary L.; Lomnicky, G.A.; Liss, W.J.; Deimling, E.

    1999-01-01

    A basic knowledge of the physical and chemical characteristics of lakes is needed by management to make informed decisions to protect water resources. In this study we investigated some of the physical and chemical characteristics of 58 lakes in alpine, subalpine, and forest vegetation zones in a natural area (North Cascades National Park Service Complex) between 1989 and 1993. The objectives of the study were to: (1) document the time of ice-out relative to lake elevation; (2) determine how a sharp climate gradient west and east of the hydrologic divide affected the time of ice-out for subalpine lakes; and (3) assess how lake water quality was associated with lake elevation, lake depth, and basin geology. As expected, lake ice-out times occurred earlier with decreasing elevation. East-slope subalpine lakes iced-out earlier than did west-slope subalpine lakes because the east slope of the study area was drier and warmer than the west slope. On average, the lakes were relatively cold, neutral in pH, and low in dissolved substances and concentrations of nitrogen and phosphorus. Although some shallow lakes (depth ,10 m) exhibited the highest alkalinities, conductivities, and concentrations of phosphorus and nitrogen, most shallow lakes exhibited low values for these variables that were comparable to values observed in deep lakes. Geology did not play a major role in segregating the lakes based on water quality. Overall, lake temperature, pH, alkalinity, conductivity, and concentrations of total phosphorus and total Kjeldahl N increased with decreasing elevation. These changes in water quality with decreasing elevation in this temperate mountainous region corresponded with warmer air temperatures and increased vegetation biomass, soil depth and maturity, and dissolved substances and nutrients.

  18. Fluid-absent metamorphism in the Adirondacks

    NASA Technical Reports Server (NTRS)

    Valley, J. W.

    1986-01-01

    Results on late Proterozoic metamorphism of granulite in the Adirondacks are presented. There more than 20,000 sq km of rock are at granulite facies. Low water fugacites are implied by orthopyroxene bearing assemblages and by stability of k'spar-plag-quartz assemblages. After mentioning the popular concept of infiltration of carbon dioxide into Precambrian rocks and attendent generation of granulite facies assemblages, several features of Adirondack rocks pertinent to carbon dioxide and water during their metamorphism are summarized: wollastonite occurs in the western lowlands; contact metamorphism by anorthosite preceeding granulite metamorphism is indicated by oxygen isotopes. Oxygen fugacity lies below that of the QFM buffer; total P sub water + P sub carbon dioxide determined from monticellite bearing assemblages are much less than P sub total (7 to 7.6 kb). These and other features indicate close spatial association of high- and low-P sub carbon dioxide assemblages and that a vapor phase was not present during metamorphism. Thus Adirondack rocks were not infiltrated by carbon dioxide vapor. Their metamorphism, at 625 to 775 C, occurred either when the protoliths were relatively dry or after dessication occurred by removal of a partial melt phase.

  19. Comparison of MAGIC and Diatom paleolimnological model hindcasts of lakewater acidification in the Adirondack region of New York

    SciTech Connect

    Sullivan, T.J.; Bernert, J.A.; Eliers, J.M. ); Jenne, E.A. ); Cosby, B.J. . School of Forestry and Environmental Studies); Charles, D.F.; Selle, A.R. . Environmental Research Lab.)

    1991-03-01

    Thirty-three lakes that had been statistically selected as part of the US Environmental Protection Agency's Eastern Lake Survey and Direct Delayed Response Project (DDRP) were used to compare the MAGIC (watershed) and Diatom (paleolimnological) models. The study lakes represented a well-defined group of Adirondack lakes, each larger than 4 ha in area and having acid-neutralizing capacity (ANC) <400 {mu}eq L{sup {minus}1}. The study first compared current and pre-industrial (before 1850) pH and ANC estimates from Diatom and MAGIC as they were calibrated in the preceding Paleocological Investigation of Recent Lake Acidification (PIRLA) and DDRP studies, respectively. Initially, the comparison of hindcasts of pre-industrial chemistry was confounded by seasonal and methodological differences in lake chemistry data used in calibration of the model. Although certain differences proved to be of little significance for comparison, MAGIC did predict significantly higher pre-industrial ANC and pH values than did Diatom, using calibrations in the preceding studies. Both models suggest acidification of low ANC Adirondack region lakes since preindustrial times, but differ primarily in that MAGIC inferred greater acidification and that acidification has occurred in all lakes in the comparison, whereas Diatom inferred that acidification has been restricted to low ANC lakes (

  20. Interpretation of gravity anomalies in the northwest Adirondack lowlands, northern New York

    SciTech Connect

    Revetta, F.A.; O'Brian, B. . Geology Dept.)

    1993-03-01

    Twelve hundred gravity measurements were made in the Adirondack Highlands and northwest Adirondack Lowlands, New York between 44[degree]15 minutes and 44[degree]30 minutes N. Latitude and 75[degree]00 minutes W. Longitude. A Bouguer gravity map constructed from the gravity measurements includes the Carthage-Colton Mylonite Zone, a major structural boundary between the highlands and lowlands. The gravity map indicates the gravity contours trend parallel to the CCMZ along most of its length however in some areas the contours cross the boundary. No clear-cut relationships exists between the CCMZ and gravity contours. The Bouguer gravity map shows several prominent gravity anomalies which correlate with the geology seismicity and mineral deposits in the area. Gravity lows of 20 to 30 g.u. are centered over the Gouverneur, Hyde and Payne Lake Alaskite gneiss bodies. A gravity high of 20 g.u. occurs over the Pleasant Lake gabbro pluton. Gravity highs of 35 and 100 g.u. occur over the Sylvia Lake Zinc District and marble just north of the district. A gravity high at Russell, N.Y. coincides with a cluster of nine earthquake epicenters. Finally a steep gravity gradient separates high density rocks from lower density rocks along the Black Lake fault. Two-dimensional computer modeling of the geologic features is underway and quantitative models of the structures will be presented.

  1. U-Pb age of the Diana Complex and Adirondack granulite petrogenesis

    USGS Publications Warehouse

    Basu, A.R.; Premo, W.R.

    2001-01-01

    U-Pb isotopic analyses of eight single and multi-grain zircon fractions separated from a syenite of the Diana Complex of the Adirondack Mountains do not define a single linear array, but a scatter along a chord that intersects the Concordia curve at 1145 ?? 29 and 285 ?? 204 Ma. For the most concordant analyses, the 207Pb/206Pb ages range between 1115 and 1150 Ma. Detailed petrographic studies revealed that most grains contained at least two phases of zircon growth, either primary magmatic cores enclosed by variable thickness of metamorphic overgrowths or magmatic portions enclosing presumably older xenocrystic zircon cores. The magmatic portions are characterized by typical dipyramidal prismatic zoning and numerous black inclusions that make them quite distinct from adjacent overgrowths or cores when observed in polarizing light microscopy and in back-scattered electron micrographs. Careful handpicking and analysis of the "best" magmatic grains, devoid of visible overgrowth of core material, produced two nearly concordant points that along with two of the multi-grain analyses yielded an upper-intercept age of 1118 ?? 2.8 Ma and a lower-intercept age of 251 ?? 13 Ma. The older age is interpreted as the crystallization age of the syenite and the younger one is consistent with late stage uplift of the Appalachian region. The 1118 Ma age for the Diana Complex, some 35 Ma younger than previously believed, is now approximately synchronous with the main Adirondack anorthosite intrusion, implying a cogenetic relationship among the various meta-igneous rocks of the Adirondacks. The retention of a high-temperature contact metamorphic aureole around Diana convincingly places the timing of Adirondack regional metamorphism as early as 1118 Ma. This result also implies that the sources of anomalous high-temperature during granulite metamorphism are the syn-metamorphic intrusions, such as the Diana Complex.

  2. Tertiary sedimentation along the Lake Mead fault system, Virgin Mountains, Nevada-Arizona

    SciTech Connect

    Beard, L.S. ); Ward, S. . Dept. of Geology)

    1993-04-01

    Sedimentary rocks of the Thumb and Rainbow Gardens Members of the Tertiary Horse Spring Formation crop out within the Virgin and South Virgin Mountains in Nevada-Arizona. The Virgins are cut by a broad zone of northeast-striking left-lateral and north-striking normal faults collectively part of the Lake Mead oblique left-lateral fault system (LMFS). Horse Spring rocks are faulted and variably eastward tilted (10--50[degree]) within the LMFS and extend northward from the Gold Butte left-lateral fault across the Lime Ridge left-lateral fault to the south flank of the Virgin Mountains. The Rainbow Gardens Member (24--18 Ma) was deposited in a shallow basin; gradual facies changes show no influence of active faulting. In contrast, lateral and vertical facies in the Thumb (16--14) Ma change abruptly and are strongly influenced by oblique-slip faulting and uplift. An unconformity separates pedogenically altered limestone of the Rainbow Gardens from overlying well-bedded lacustrine limestones of the Thumb. Locally the unconformity is overlain by conglomerate and megabreccia deposits composed of underlying Rainbow Gardens carbonate clasts derived from energy fault scarps. Thumb carbonates above the unconformity grade laterally and vertically into thick deposits of lacustrine gypsum and fine-grained sandstone, which in turn intertongue laterally and vertically with marginal lake and alluvial fan facies. Abrupt influx of megabreccia and coarse conglomerate into Thumb lacustrine deposits northward from both the Gold Butte and Lime Ridge faults indicates continued faulting.

  3. Ammonia uptake by phytoplankton and limnological studies of Mountain Lake, Virginia

    SciTech Connect

    Parson, J.J.

    1988-01-01

    The first comprehensive year-round investigation of Mountain Lake, Virginia since 1970-71 was begun in March 1985 and continued through November 1987. Whereas inorganic nitrogen, orthophosphate, Secchi disc transparency, and primary productivity continue to suggest an oligotrophic condition, important limnological changes are indicated by the greater seasonal hypolimnetic oxygen depletion and extractable chlorophyll a which at times approach mesotrophic levels. In addition, the decrease in alkalinity, the increase in sulfate levels, and the increase in pH fluctuations compared to the past, suggest that Mountain Lake is susceptible to damage or change by acid rain and perhaps other perturbations that effect pH alkalinity or hardness. Changes were also noted in phytoplankton composition. Studies of ammonia uptake by the phytoplankton, using the ammonia analog ({sup 14}C)methylamine (MeA), revealed that during thermal stratification, phytoplankton succession was related to rapid ammonia uptake. Each successive phytoplankton community had significantly higher Vmax values for ammonia (methylamine) until midsummer when ammonia-nitrogen levels were at a seasonal low.

  4. [Distribution of Chlorophyll-a and Eutrophication State in Tianchi Lake of Tianshan Mountains in Summer].

    PubMed

    Wang, Bin; Ma, Jian; Wang, Yin-ya; Yin, Xiang-jiang

    2015-07-01

    From June to August in 2014, the distributions of chlorophyll-a (Chl-a) and correlations with environmental factors were investigated, the eutrophication status and causes were discussed in Tianchi Lake of Tianshan Mountains. The results showed that the Chl-a concentrations ranged from 2. 11 to 4. 06 µg. L -1 with a mean value of (2. 8 ± 0. 69) µg . L-1 in summer, the vertical distribution of Chl-a in different monitoring zones had a similar characteristic that the Chl-a concentration in epilimnionis (2-12 m) was higher than those at the surface (0-2 m) and hypolimnion (below 12 m). The Chl-a concentration had significant negative correlations with depth and conductivity, significant positive correlations with water temperature, pH value, the concentration of dissolved oxygen, the cell density of algae and TP, and less correlation with TN. The mean concentrations of TN and TP in Tianchi Lake in summer were 0.27 mg . L-1 and 0.035 mg. L-1 respectively, both of which exceeded the international standards of general eutrophic lakes. The modified Carlson trophic state index was used to assess the eutrophication status of Tianchi Lake, which is currently at a moderate eutrophication level. The reasons might be the increased nutrients attributed to soil erosion, and algae blooms due to the changes in the composition of hydrobios. Therefore, it is important to use ecological restoration and management to protect the water quality and surrounding vegetation, which may mitigate the risk of eutrophication in Tianchi Lake.

  5. Source limitation of carbon gas emissions in high-elevation mountain streams and lakes

    NASA Astrophysics Data System (ADS)

    Crawford, John T.; Dornblaser, Mark M.; Stanley, Emily H.; Clow, David W.; Striegl, Robert G.

    2015-05-01

    Inland waters are an important component of the global carbon cycle through transport, storage, and direct emissions of CO2 and CH4 to the atmosphere. Despite predictions of high physical gas exchange rates due to turbulent flows and ubiquitous supersaturation of CO2—and perhaps also CH4—patterns of gas emissions are essentially undocumented for high mountain ecosystems. Much like other headwater networks around the globe, we found that high-elevation streams in Rocky Mountain National Park, USA, were supersaturated with CO2 during the growing season and were net sources to the atmosphere. CO2 concentrations in lakes, on the other hand, tended to be less than atmospheric equilibrium during the open water season. CO2 and CH4 emissions from the aquatic conduit were relatively small compared to many parts of the globe. Irrespective of the physical template for high gas exchange (high k), we found evidence of CO2 source limitation to mountain streams during the growing season, which limits overall CO2 emissions. Our results suggest a reduced importance of aquatic ecosystems for carbon cycling in high-elevation landscapes having limited soil development and high CO2 consumption via mineral weathering.

  6. Transport of pollutants from cow feedlots in eastern Colorado into Rocky Mountain alpine lakes

    NASA Astrophysics Data System (ADS)

    Pina, A.; Denning, S.; Schumacher, R. S.

    2012-12-01

    Concentrated Animal Feeding Operations (CAFOs), also called factory farms, are known for raising tens of millions head of livestock including cows (beef and dairy), swine, and poultry. With as many as 250 head of cattle per acre, a United States Department of Agriculture's (USDA) Agricultural Research Service (ARS) report showed beef cattle from CAFOs in the United States produce as much as 24.1 million tons of manure annually. Gases released from cow manure include methane (CH4), nitrous oxide (N2O), hydrogen sulfide (H2S), and ammonia (NH3). During boreal summers Colorado experiences fewer synoptic weather systems, allowing the diurnal cycle to exert greater control of meteorological events along the mountain-plains interface. Anabatic, or upslope winds induced by the diurnal cycle, contribute largely to the transport of gases and particulates from feedlots in eastern Colorado into the Rocky Mountains, presenting a potential harm to natural alpine ecosystems. This study focuses on locating the source of transport of gases from feedlots along the eastern Front Range of Colorado into alpine lakes of the Rocky Mountains. Source regions are approximated using backward time simulation of a Lagrangian Transport model.

  7. Source limitation of carbon gas emissions in high-elevation mountain streams and lakes

    USGS Publications Warehouse

    Crawford, John T.; Dornblaser, Mark M.; Stanley, Emily H.; Clow, David W.; Striegl, Robert G.

    2015-01-01

    Inland waters are an important component of the global carbon cycle through transport, storage, and direct emissions of CO2 and CH4 to the atmosphere. Despite predictions of high physical gas exchange rates due to turbulent flows and ubiquitous supersaturation of CO2—and perhaps also CH4—patterns of gas emissions are essentially undocumented for high mountain ecosystems. Much like other headwater networks around the globe, we found that high-elevation streams in Rocky Mountain National Park, USA, were supersaturated with CO2 during the growing season and were net sources to the atmosphere. CO2concentrations in lakes, on the other hand, tended to be less than atmospheric equilibrium during the open water season. CO2 and CH4 emissions from the aquatic conduit were relatively small compared to many parts of the globe. Irrespective of the physical template for high gas exchange (high k), we found evidence of CO2 source limitation to mountain streams during the growing season, which limits overall CO2emissions. Our results suggest a reduced importance of aquatic ecosystems for carbon cycling in high-elevation landscapes having limited soil development and high CO2 consumption via mineral weathering.

  8. Mountain Lake, Presidio National Park, San Francisco: Paleoenvironment, heavy metal contamination, sedimentary record rescue, remediation, and public outreach

    NASA Astrophysics Data System (ADS)

    Myrbo, A.; Rodysill, J. R.; Jones, K.; Reidy, L. M.

    2014-12-01

    Sediment cores from Mountain Lake, a small natural lake in Presidio National Park, San Francisco, CA, provide a record of Bay Area environmental change spanning the past 2000 years, and of unusually high heavy metal contamination in the last century (Reidy 2001). In 2013, partial dredging of the lake removed the upper two meters of lake sediment as part of a remediation effort. Prior to dredging, long and short cores spatially covering the lake and representing deep and shallow environments were recovered from the lake to preserve the paleoenvironmental record of one of the only natural lakes on the San Francisco Peninsula. The cores are curated at LacCore and are available for research by the scientific community. Mountain Lake formed in an interdunal depression and was shallow and fluctuating in its first few hundred years. Lake level rise and inundation of a larger area was followed by lowstands under drier conditions around 550-700 and 1300 CE. Nonnative taxa and cultivars appeared at the time of Spanish settlement in the late 18th century, and the lake underwent eutrophication due to livestock pasturing. U.S. Army landscaping introduced trees to the watershed in the late 19th century. The upper ~1m of sediments document unusually high heavy metal contamination, especially for lead and zinc, caused by the construction and heavy use of Highway 1 on the lake shore. Lead levels peak in 1975 and decline towards the surface, reflecting the history of leaded gasoline use in California. Zinc is derived mainly from automobile tires, and follows a pattern similar to that of lead, but continues to increase towards the surface. Ongoing research includes additional radiocarbon dating and detailed lithological analysis to form the basis of lake-level reconstruction and archeological investigations. Because the Presidio archaeological record does not record human habitation in the area until approximately 1300 years before present, the core analysis also has the potential to

  9. Arsenic, cobalt and chromium food web biodilution in a Patagonia mountain lake.

    PubMed

    Revenga, J E; Campbell, L M; Arribére, M A; Ribeiro Guevara, S

    2012-07-01

    Mussels, Diplon chilensis, from Lake Moreno, a double-basined mountain lake in southern Argentina, is known to have elevated concentrations of chromium (Cr, > 25 μg g⁻¹ dry weight DW) and arsenic (As, 35 μg g⁻¹ DW), attributed to untreated sewage. To further understand the trophodynamics of Cr, As and cobalt (Co), we investigated concentrations and transfer throughout the food web in each basin of Lake Moreno. Each basin differs in morphology in that the gently-sloping Lake Moreno West has more littoral habitat than deeper Lake Moreno East with its higher proportion of pelagic habitat. Despite the morphological differences, both basins share similar water quality parameters and species assemblages. As a result, Lake Moreno provides an exceptional opportunity to compare trophodynamics of elements that enable us to hypothesize pelagic-littoral habitat coupling in response to lake morphology as the underlying factor influencing both Cr pathway and Co and As trophodynamic modeling. Using stable isotopes of nitrogen (δ¹⁵N) and carbon (δ¹³C) to characterize metals trophodynamics in each basin, biodilution of As, Cr and Co were indicated by negative regressions. This is confirmed by elevated As, Co and Cr concentrations in phytoplankton (11.3±5.7, 7.4±4.9, 44.5±40.7 μg g⁻¹ DW respectively), while zooplankton and biofilm had the next elevated concentrations. Those elevated concentrations are in contrast with lower concentrations in sport fish such as rainbow trout (0.5±0.5, 0.2±0.3, 1.8±1.2 μg g⁻¹ DW). Higher concentrations of Cr in fish were associated with higher proportion of benthic/littoral prey items in western basin, and were confirmed by significant correlation with δ¹³C values. Arsenic, Co and Cr concentrations in fish, while elevated, do not post health risks to human or wildlife consumers.

  10. Paired moraine-dammed lakes: a key landform for glaciated high mountain areas in the tropical Andes of Peru

    NASA Astrophysics Data System (ADS)

    Iturrizaga, Lasafam

    2016-04-01

    The tropical mountain range of the Cordillera Blanca hosts one of the main concentrations of proglacial lakes in high-mountain settings worldwide, which have formed as a result of the dominant trend of modern glacier retreat. Based on empirical data from field research in over 20 valleys and the analysis of air and satellite images, a genetic classification of major lake types with their barriers and a generalized model for the distribution of the present lakes and paleolakes was set up. The origin of the lakes and their recurrent distribution pattern are associated with the individual stages of the Pleistocene to modern glaciation and their corresponding geomorphological landforms. Characteristic repetitive moraine sequences are found in the upper parts of numerous valleys of the Cordillera Blanca. In terms of the spatial arrangement of the lake types, combined lakes are classified as a distinct composite lake type. These lakes occur at nearly the same elevation or at successively lower elevations, and form characteristic lake sequences of two or more lakes. They may occur as multi-moraine-dammed lakes or mixed combined lakes such as moraine-rock-dammed lakes or multi-debris-dammed lakes. From special interest are in this study the paired moraine-dammed lakes (e.g. Lagunas Qoyllurcochas, Lagunas Safuna Alta and Baja). They are composed of the Great Endmoraine (GEM), primarily formed during the Little Ice Age and earlier, and the pre-GEM, formed during the Holocene. Both moraines are located in rather close vicinity to each other at a distance of 1-3 km. In contrast to the prominent sharp-crested GEM, the pre-GEM is a low-amplitude end-moraine complex, which usually does not exceed a few meters to tens of meters in height. The latter is often composed of several inserted moraine ridges or an irregular hummocky moraine landscape. It is argued here that the process of formation of these combined lakes is mainly controlled by a combination of distinct topographical

  11. Ion chromatographic determination of lithium at trace level concentrations. Application to a tracer experiment in a high-mountain lake.

    PubMed

    Nickus, U; Thies, H

    2001-06-22

    The water residence time of a high-mountain seepage lake in the Austrian Alps was derived from the flushing rate of a tracer substance. A diluted lithium chloride solution was injected into the lake during holomictic conditions in order to favour the homogeneous distribution of the tracer. The exponential decline of the mass of lithium in the lake revealed a water residence time of 1.5 to 3 months for summer and almost no lake water exchange during winter. Lithium concentrations ranged from background values of 0.06 microg l(-1) to about 3 microg l(-1) immediately after the tracer injection. Lake water samples were analyzed with ion-exchange chromatography using a Dionex device with a CS 12A separation column. The method detection limit determined according to the definition of the US Envirinmental Protection Agency amounted to 0.009 microg l(-1).

  12. Mineral and geothermal resource potential of Wild Cattle Mountain and Heart Lake roadless areas Plumas, Shasta, and Tehama Counties, California

    SciTech Connect

    Muffler, L.J.P.; Clynne, M.A.; Cook, A.L.

    1982-01-01

    The results of geological, geochemical, and geophysical surveys in Wild Cattle Mountain and Heart Lake Roadless Areas indicate no potential for metallic or non-metallic mineral resources in the areas and no potential for coal or petroleum energy resources. However, Wild Cattle Mountain Roadless Area and part of Heart Lake Roadless Area lie in Lassen Known Geothermal Resources Area, and much of the rest of Heart Lake Roadless Area is subject to non-competitive geothermal lease applications. Both areas are adjacent to Lassen Volcanic National Park, which contains extensive areas of fumaroles, hot springs, and hydrothermally altered rock; voluminous silicic volcanism occurred here during late Pleistocene and Holocene time. Geochemical data and geological interpretation indicate that the thermal manifestations in the Park and at Morgan and Growler Hot Springs (immediately west of Wild Cattle Mountain Roadless Area) are part of the same large geothermal system. Consequently, substantial geothermal resources are likely to be discovered in Wild Cattle Mountain Roadless Area and cannot be ruled out for Heart Lake Roadless Area.

  13. Chemical quality of water, sediment, and fish in Mountain Creek Lake, Dallas, Texas, 1994-97

    USGS Publications Warehouse

    Van Metre, Peter C.; Jones, S.A.; Moring, J. Bruce; Mahler, B.J.; Wilson, Jennifer T.

    2003-01-01

    The occurrence, trends, and sources of numerous inorganic and organic contaminants were evaluated in Mountain Creek Lake, a reservoir in Dallas, Texas. The study, done in cooperation with the Southern Division Naval Facilities Engineering Command, was prompted by the Navy’s concern for potential off-site migration of contaminants from two facilities on the shore of Mountain Creek Lake, the Naval Air Station Dallas and the Naval Weapons Industrial Reserve Plant. Sampling of stormwater (including suspended sediment), lake water, bottom sediment (including streambed sediment), and fish was primarily in Mountain Creek Lake but also was in stormwater outfalls from the Navy facilities, nearby urban streams, and small streams draining the Air Station.Volatile organic compounds, predominantly solvents from the Reserve Plant and fuel-related compounds from the Air Station, were detected in stormwater from both Navy facilities. Fuel-related compounds also were detected in Mountain Creek Lake at two locations, one near the Air Station inlet where stormwater from a part of the Air Station enters the lake and one at the center of the lake. Concentrations of volatile organic compounds at the two lake sites were small, all less than 5 micrograms per liter.Elevated concentrations of cadmium, chromium, copper, lead, mercury, nickel, silver, and zinc, from 2 to 4 times concentrations at background sites and urban reference sites, were detected in surficial bottom sediments in Cottonwood Bay, near stormwater outfalls from the Reserve Plant. Elevated concentrations of polycyclic aromatic hydrocarbons and polychlorinated biphenyls, compared to background and urban reference sites, were detected in surficial sediments in Cottonwood Bay. Elevated concentrations of polycyclic aromatic hydrocarbons, indicative of urban sources, also were detected in Cottonwood Creek, which drains an urbanized area apart from the Navy facilities. Elevated concentrations of polychlorinated biphenyls were

  14. The first detection of potentially toxic Microcystis strains in two Middle Atlas Mountains natural lakes (Morocco).

    PubMed

    Douma, Mountasser; Ouahid, Youness; Loudiki, Mohammed; Del Campo, Francisca F; Oudra, Brahim

    2017-01-01

    Aguelmam Azizgza (LAZ) and Dayet Afourgah (DAF) are two Moroccan natural lakes located in a humid hydrographic basin of the Middle Atlas Mountains. Both are considered important reservoirs of plant and animal biodiversity. In addition, they are extensively used for recreational and fishing activities and as a water source for irrigation of agricultural crops. Recurrent cyanobacteria scum episodes in the two water bodies have been reported, Microcystis being the main genus in the scums. Here, we report on the toxic potential of three Microcystis aeruginosa strains isolated from those lakes: Mic LAZ and Mic B7 from LAZ and Mic DAF isolated from DAF. The toxic potential was checked by their microcystin (MC) content and the presence of mcy genes involved in MC synthesis. The identification and quantification of MC variants were performed by high-performance liquid chromatography-photo-diode array. The detection of mcy genes was achieved by whole-cell multiplex PCR that allowed the simultaneous amplification of DNA sequences corresponding to specific mcy regions. MC content of cultured cells, as MC-LR equivalents per gram cell biomass, was slightly higher in Mic LAZ (ca. 860) than in Mic B7 (ca. 700) and Mic DAF (ca. 690). Four MC variants were identified in the three isolates: MC-WR, MC-RR, MC-DM-WR, and MC-YR. The presence of toxic Microcystis strains in the two studied lakes may be regarded as an environmental and health hazard, especially during periods of bloom proliferation. It would be recommended the use of two complementary techniques, as those utilized herein (HPLC and mcy detection) to alert on highly probable toxicity of such lakes.

  15. Wetland vegetation responses to liming an Adirondack watershed

    SciTech Connect

    Mackun, I.R.

    1993-01-01

    Watershed liming as a long-term mitigation strategy to neutralize lake acidity, from increasing acid deposition, was initiated in North America at Woods Lake in the west central Adirondack region of New York. In October 1989, a dose of 10 MT lime (83.5% CaCO[sub 3]) ha[sup [minus]1] was aerially applied to 48% of the watershed. The wetlands adjacent to Woods Lake showed two distinct community types: one dominated by Chamaedaphne calyculata, and one dominated by graminoids and other herbaceous species. Within two years, liming did not alter the structure of either community type, and changed the cover or frequency of only 6 of 64 individual taxa. Most of these changes occurred in the herbaceous community type. The only strong positive response to liming was a nearly threefold increase in cover of the rhizomatous sedge Cladium mariscoides. The cover of Carex interior and Sphagnum spp. benefited from lime addition, while cover of Drosera intermedia and Muhlenbergia uniflora, and frequency of Hypericum canadense responded negatively to lime. Liming influenced the competitive release of only three taxa, all forbs with small growth forms. The tissue chemistry of foliage and twigs of Myrica gale, Chamaedaphne calyculata, and Carex stricta in the Chamaedaphne calyculata community type clearly illustrated species-specific patterns of nutrient accumulation and allocation both before and after liming. Concentrations of 17 of 20 elements responded to liming, although the responses varied among species and plant parts. Carex foliage was least responsive to liming, and Chamaedaphne twigs were most responsive. Elemental changes in plant tissues will be reflected in litter and many influence long-term nutrient dynamics in the wetland community.

  16. Late Holocene climate change at Goat Lake, Kenai Mountains, south-central Alaska

    NASA Astrophysics Data System (ADS)

    Daigle, T. A.; Kaufman, D. S.

    2006-12-01

    Lake sediments, glacier extents, and tree rings were used to reconstruct late Holocene climate changes from Goat Lake in the Kenai Mountains, south-central Alaska (60° 14' N/149° 54' W). Two sediment cores (3.7 and 5.6 m long) were dated with 16 AMS 14C ages and record changes in watershed (organic- matter content) and within-lake (biogenic silica) productivity since ~9500 cal yr BP. Sediment analyses focused on the last 1000 yr; this interval includes a sharp transition from gyttja to inorganic mud at ~1660 AD, which marks the fist time since Pleistocene deglaciation that the north goat outlet glacier (NGO) of the Harding Icefield overtopped the drainage divide at 590 m asl to spill meltwater into Goat Lake. One 14C age of ~1535 AD from a subfossil log in the NGO valley requires ~125 yr for the NGO to thicken 150 m to the elevation of the drainage divide where it remained until ~1930. Since ~1930, the NGO has thinned 150 m and retreated 1.4 km. Equilibrium-line altitudes (ELA) were reconstructed for 12 cirque glaciers nearby Goat Lake based on the accumulation-area ratio (AAR) method following field mapping of ice-marginal features formed during the maximum Little Ice Age (LIA) in the 19th century. Maximum LIA ELA data (AAR = 0.58) were compared with 1950 ELA and yield an average lowering of 50 ± 20 m. Application of the local lapse rate of 0.47°C/100 m indicates an average ablation-season temperature reduction of 0.3°C during the maximum LIA compared to 1950, assuming no change in winter precipitation. A new tree-ring chronology from 27 hemlock trees in the Goat Lake watershed correlates with mean March through August temperature from Kenai airport (r = 0.35) and a 207 yr reconstruction indicates an average temperature reduction of 1.0°C from 1800-1900 compared with 1930-1950. Assuming no change in winter precipitation, then a 1°C cooling should have been associated with an ELA lowering by 200 m. This did not occur, and we suggest that some degree of

  17. An investigation of the origin of Rock City and cause of piping problems at Mountain Lake, Giles County, Virginia

    NASA Astrophysics Data System (ADS)

    Atallah, Nidal Walid

    Mountain Lake is one of only two natural lakes in the state of Virginia. The lake's origin has been attributed to either a natural solution-collapse basin, or to a landslide damming the valley of northwesterly flowing Pond Drain, or to a NW-SE trending fracture lineation. The lake is located within the breached northwest limb of a gently plunging anticline, a part of the larger Valley and Ridge physiographic province. In recent years, the lake drained almost completely, exposing the lake bottom and revealing the presence of four sinkhole-like depressions, containing piping holes at their sides and bottoms, at the northeastern and northwestern margins of the lake. This study focuses on the most likely origin of large sandstone blocks present at the northern end of the lake in an area locally referred to as "Rock City", including mapping of the block locations and analyzing the mode and extent of displacement that they have undergone. An additional objective is to investigate the piping potential of the lake-bottom sediment and its role in seepage out of the lake basin causing lake-level fluctuations. Mapping of Rock City was conducted by taking GPS readings at the corners of the rock blocks and using ArcMap Software. Investigations of the displacement mode of the rock blocks was done by comparing the measured orientations of principal discontinuity sets, forming the rock-block boundaries, with discontinuity orientations of undisturbed outcrops within the headscarp, using stereonet analysis. Grain size analysis, Atterberg limits, and a compaction-mold permeameter test were used to evaluate lake sediment's susceptibility to piping. Field observations and discontinuity data analysis indicate that Rock City is a landslide that dammed the valley of Pond Drain, consequently forming the lake. The primary mode of slope movement involves lateral spreading that is associated with extension occurring along discontinuities. The Tuscarora Sandstone rock blocks comprising Rock

  18. Analyses and descriptions of geochemical samples, Mountain Lake Wilderness Study Area, Virginia and West Virginia

    USGS Publications Warehouse

    Mei, Leung; Fletcher, J.D.; Rait, Norma; Lesure, F.G.

    1978-01-01

    Semiquantitative emission spectrographic analyses for 64 elements on 95 stream sediment and 122 rock samples from Mountain Lake Wilderness Study Area, Giles and Craig Counties, Virginia and Monroe County, West Virginia, are reported here in detail. Locations for all samples are in Universal Transverse Mercator (UTM) coordinates. Brief descriptions of rock samples are also included. Rocks analysed are mostly sandstone. Samples of hematitic sandstone of the Rose Hill Formation and limonite-cemented sandstone of the Rocky Gap Sandstone contain high values of iron; these rocks are submarginal iron resources. Some of these iron-rich samples have a little more barium, copper, cobalt, lead, silver, and/or zinc than in average sandstone, but they do not suggest the presence of economic deposits of these metals. A few samples of Tuscarora Quartzite contain moderate amounts of manganese. These are from a submarginal manganese resource. No other obviously anomalous-values related to mineralized rock are present in the data.

  19. Holocene lake level fluctuations of a small alpine lake in the Qilian Mountains, NW China: a comparison of chironomid, ostracod, pollen and geochemistry data.

    NASA Astrophysics Data System (ADS)

    Mischke, S.; Herzschuh, U.

    2003-04-01

    A core of 14 m length was drilled in a small alpine lake in the Qilian Mountains, NW China. The lake Luanhaizi has a drainage area of about 30 km2 and is situated at an altitude of 3200 m which represents the altitude of the present regional upper timberline. Due to the small size of the open-basin lake (surface area about 1 km2) and the sharply outlined catchment area the lake is regarded as a very sensitively and rapidly responding ecosystem. Analyses of ostracod shells, head capsules of larval chironomids and pollen and spores were conducted and the organic and carbonate content (LOI), element concentrations and magnetic susceptibility of core samples determined. Ostracod taxa mainly comprise Candona candida, C. neglecta, C. rawsoni, Cyclocypris ovum, Cypridopsis vidua, Fabaeformiscandona caudata, F. danielopoli, F. hyalina, Herpetocypris chevreuxi, Heterocypris salina, Ilyocypris cf. bradyi, I. echinata, I. lacustris and Limnocythere inopinata. They may be used to distinguish periods of low lake levels corresponding to a dense cover of aquatic plants at the lake bottom from stages of higher lake levels and a corresponding decrease in macrophytes at the core site. Chironomid taxa belonging to Chironomus, Cladopelma, Glyptotendipes, Micropsectra, Paratanytarsus, Polypedilum, Psectrocladius and Tanytarsus further provide information on variations in benthic oxygen availability and lake level fluctuations. Several units of the core show high abundances of pollen and spores of higher aquatic and wetland plants and fungi (Cyperaceae, Hippuris, Myriophyllum and Glomus) indicating low lake levels. In contrast, algae such as Botryococcus, Pediastrum and Tetraedron were regarded to reflect higher water levels. Typha angustifolia-type, Typha latifolia, Alisma and Potamogeton were recorded in low abundances as well. The organic content of core samples averages 6 % displaying four alternating stages of distinct minima and maxima. Lowest values of about 1 % occur at the core

  20. Environmental factors prevail over dispersal constraints in determining the distribution and assembly of Trichoptera species in mountain lakes

    PubMed Central

    de Mendoza, Guillermo; Ventura, Marc; Catalan, Jordi

    2015-01-01

    Aiming to elucidate whether large-scale dispersal factors or environmental species sorting prevail in determining patterns of Trichoptera species composition in mountain lakes, we analyzed the distribution and assembly of the most common Trichoptera (Plectrocnemia laetabilis, Polycentropus flavomaculatus, Drusus rectus, Annitella pyrenaea, and Mystacides azurea) in the mountain lakes of the Pyrenees (Spain, France, Andorra) based on a survey of 82 lakes covering the geographical and environmental extremes of the lake district. Spatial autocorrelation in species composition was determined using Moran’s eigenvector maps (MEM). Redundancy analysis (RDA) was applied to explore the influence of MEM variables and in-lake, and catchment environmental variables on Trichoptera assemblages. Variance partitioning analysis (partial RDA) revealed the fraction of species composition variation that could be attributed uniquely to either environmental variability or MEM variables. Finally, the distribution of individual species was analyzed in relation to specific environmental factors using binomial generalized linear models (GLM). Trichoptera assemblages showed spatial structure. However, the most relevant environmental variables in the RDA (i.e., temperature and woody vegetation in-lake catchments) were also related with spatial variables (i.e., altitude and longitude). Partial RDA revealed that the fraction of variation in species composition that was uniquely explained by environmental variability was larger than that uniquely explained by MEM variables. GLM results showed that the distribution of species with longitudinal bias is related to specific environmental factors with geographical trend. The environmental dependence found agrees with the particular traits of each species. We conclude that Trichoptera species distribution and composition in the lakes of the Pyrenees are governed predominantly by local environmental factors, rather than by dispersal constraints. For

  1. An Investigation of the Impacts of Climate and Environmental Change on Alpine Lakes in the Uinta Mountains, Utah

    NASA Astrophysics Data System (ADS)

    Moser, K. A.; Hundey, E. J.; Porinchu, D. F.

    2007-12-01

    Aquatic systems in alpine and sub-alpine areas of the western United States are potentially impacted by atmospheric pollution and climate change. Because these mountainous regions are an important water resource for the western United States, it is critical to monitor and protect these systems. The Uinta Mountains are an east- west trending mountain range located on the border between Utah, Wyoming and Colorado and downwind of the Wasatch Front, Utah, which is characterized by a rapidly expanding population, as well as mining and industry. This alpine area provides water to many areas in Utah, and contributes approximately nine percent of the water supply to the Upper Colorado River. Our research is focused on determining the impacts of climate change and pollution on alpine lakes in the Uinta Mountains. The results presented here are based on limnological measurements made at 64 Uinta Mountain lakes spanning a longitude gradient of one degree and an elevation gradient of 3000 feet. At each lake maximum depth, conductivity, salinity, pH, Secchi depth, temperature, alkalinity, and concentrations of major anions, cations and trace metals were measured. Principal Components Analysis (PCA) was performed to determine relationships between these variables and to examine the variability of the values of these variables. Our results indicate that steep climate gradients related to elevation and longitude result in clear differences in limnological properties of the study sites, with high elevation lakes characterized by greater amounts of nitrate and nitrite compared to low elevation sites. As well, diatoms in these lakes indicate that many high elevation sites are mesotrophic to eutrophic, which is unexpected for such remote aquatic ecosystems. We hypothesize that elevated nitrate and nitrite levels at high elevation sites are related to atmospherically derived nitrogen, but are being exacerbated relative to lower elevation sites by greater snow cover and reduced plant

  2. Genesis of recent silicic magmatism in the Medicine Lake Highland, California - Evidence from cognate inclusions found at Little Glass Mountain

    NASA Technical Reports Server (NTRS)

    Mertzman, S. A.; Williams, R. J.

    1981-01-01

    Sparse, granular inclusions of early-formed minerals found within the Little Glass Mountain rhyolite flows in northern California are shown to provide a means of characterizing the physical conditions, at depth, beneath the Medicine Lake Highland during the latest phase of volcanic activity. Mineral compositions, in combination with thermodynamic calculations and experiments, suggest crystalization at a pressure of 5,200 bars within a 966-836 C temperature range; implying that mineral segregation and equilibration occurred at a depth of 15-18 km beneath the surface. In addition, mass balance calculations indicate that the Medicine Lake flow is a close approximation to the parental magma for the latest silicic lavas.

  3. Evolution and hazard analysis of high-mountain lakes in the Cordillera Vilcabamba (Southern Peru) from 1991 to 2014

    NASA Astrophysics Data System (ADS)

    Guardamino, Lucía; Drenkhan, Fabian

    2015-04-01

    In recent decades, glaciers in high-mountain regions have experienced unprecedented glacier retreat since the Little Ice Age (LIA). This development triggers the formation and growth of glacier lakes, which in combination with changes in glacier parameters might produce more frequent conditions for the occurrence of disasters, such as Glacier Lake Outburst Floods (GLOF). Facing such a scenario, the analysis of changing lake characteristics and identification of new glacier lakes are imperative in order to identify and reduce potential hazards and mitigate or prevent future disasters for adjacent human settlements. In this study, we present a multi-temporal analysis with Landsat TM 5 and OLI 8 images between 1991 and 2014 in the Cordillera Vilcabamba region (Southern Peru), a remote area with difficult access and climate and glaciological in-situ data scarcity. A semi-automatic model was developed using the band ratios Normalized Difference Snow Index (NDSI) and Normalized Difference Water Index (NDWI) in order to identify glacier and lake area changes. Results corroborate a strong glacier area reduction of about 51% from 1991 (200.3 km²) to 2014 (98.4 km²). At the same time, the number of lakes (total lake surface) has increased at an accelerated rate, from 0.77% (0.48%) in 1991 to 2.31% (2.49%) in 2014. In a multiple criteria analysis to identify potential hazards, 90 out of a total of 329 lakes in 2014 have been selected for further monitoring. Additionally, 29 population centers have been identified as highly exposed to lake related hazards from which 25 indicate a distance less than 1 km to an upstream lake and four are situated in a channel of potential debris flow. In these areas human risks are particularly high in view of a low HDI below Peru's average and hence pronounced vulnerability. We suggest more future research on measurements and monitoring of glacier and lake characteristics in these remote high-mountain regions, which include comprehensive risk

  4. Preorogenic history of the Adirondacks as an elsonian anorogenic caldera complex

    SciTech Connect

    McLelland, J.

    1985-01-01

    The Adirondack Highlands are characterized by the close association of a distinctive trinity of metaigneous rocks: (1) anorthosites, (2) mangeritic and quartz mangeritic gneisses that tend to envelop the anorthosites, and (3) alaskitic and trondjhemitic gneisses many of which represent metamorphosed volcanic material. All rocks within the province exhibit high concentrations of iron (FeO/FeO + MgO approx. 0.8), and both titaniferous and non-titaniferous iron oxide deposits occur. The mangeritic rocks are alkaline to peralkaline while the alaskitic gneisses are meta- to peraluminous. A/CNK, KN/C, as well as oxides vs SiO/sub 2/ plots yield patterns identical to those cited by J. L. Anderson (1983) as diagnostic of Proterozoic anorogenic plutonism. Within North American this plutonism corresponds to the Elsonian magmatic event with most ages falling between 1.5 - 1.3 b.y. This belt is characterized by high-level anorogenic bimodal magmatism developed in caldera complexes with zoned magma chambers and widespread rhyolitic ash-flow tuffs. Examples of this activity are found in the St. Francois Mountains, Missouri; the Wolf River batholith, Wisconsin; and the Nain Province. The Adirondacks lie along this trend and exhibit the same bulk chemistry and chemical variation as the other complexes. In addition they show enrichment in halogens (esp. F), REE, Zr, and other trace elements associated with calderas. Fayalite and ferroaugite are widely developed. These similarities strongly suggest that prior to the Grenville Orogeny, the Adirondacks consisted of bimodal caldera complexes which were part of the Elsonian anorogenic magmatism extending across North America.

  5. Chronic and episodic acidification of Adirondack streams from acid rain in 2003-2005

    USGS Publications Warehouse

    Lawrence, G.B.; Roy, K.M.; Baldigo, Barry P.; Simonin, H.A.; Capone, S.B.; Sutherland, J.W.; Nierzwicki-Bauer, S. A.; Boylen, C.W.

    2008-01-01

    Limited information is available on streams in the Adirondack region of New York, although streams are more prone to acidification than the more studied Adirondack lakes. A stream assessment was therefore undertaken in the Oswegatchie and Black River drainages; an area of 4585 km2 in the western part of the Adirondack region. Acidification was evaluated with the newly developed base-cation surplus (BCS) and the conventional acid-neutralizing capacity by Gran titration (ANCG). During the survey when stream water was most acidic (March 2004), 105 of 188 streams (56%) were acidified based on the criterion of BCS < 0 ??eq L-1, whereas 29% were acidified based on an ANCG value < 0 ??eq L-1. During the survey when stream water was least acidic (August 2003), 15 of 129 streams (12%) were acidified based on the criterion of BCS < 0 ??eq L-1, whereas 5% were acidified based on ANCG value < 0 ??eq L -1. The contribution of acidic deposition to stream acidification was greater than that of strongly acidic organic acids in each of the surveys by factors ranging from approximately 2 to 5, but was greatest during spring snowmelt and least during elevated base flow in August. During snowmelt, the percentage attributable to acidic deposition was 81%, whereas during the October 2003 survey, when dissolved organic carbon (DOC) concentrations were highest, this percentage was 66%. The total length of stream reaches estimated to be prone to acidification was 718 km out of a total of 1237 km of stream reaches that were assessed. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  6. Characterization of an organic acid analog model in Adirondack, New York, surface waters

    NASA Astrophysics Data System (ADS)

    Fakhraei, H.; Driscoll, C. T.

    2013-12-01

    Natural waters include a variety of organic matter that differs in composition and functional groups. Dissolved organic matter is important but difficult to characterize acidic and metal binding (e.g., Al) functional groups in chemical equilibrium models. In this study data from Adirondack Lake Survey were used to calibrate an organic acid analog model in order to quantify the influence of organic acids on surface water chemistry. The study sites in the Adirondack region of New York have diverse levels of dissolved organic carbon (DOC), used as a surrogate for organic acids. DOC in 55 Adirondack surface waters varies from 180 μmol C/l (in Little Echo Pond) to 1263 μmol C/l (in Sunday Pond). To reduce the variability inherited in the large raw data set, suite of mean observations was constructed by grouping and averaging measured data into pH intervals of 0.05 pH units from pH 4.15 to 7.3. A chemical equilibrium model, which includes major solutes in natural waters, was linked to an optimization algorithm (genetic algorithm) to calibrate a triprotic organic analog model which includes proton and aluminum binding by adjusting the dissociation constants and site density of DOC. The object of fitting procedure was to simultaneously minimize the discrepancy between observed and simulated pH, acid neutralizing capacity (ANC), organic monomeric aluminum and inorganic monomeric aluminum. A sensitivity analysis on calibrated values indicate that the speciation of the modeled solutes are most responsive to the dissociation constant of AlOrg= Al3+ + Org3- reaction (Org3- represents organic anion), the site density of DOC and the second H+ dissociation constant of the triprotic organic analog (i.e. H2Org- = 2H+ + Org3- reaction).

  7. Seasonal Community and Population Dynamics of Pelagic Bacteria and Archaea in a High Mountain Lake

    PubMed Central

    Pernthaler, Jakob; Glöckner, Frank-Oliver; Unterholzner, Stefanie; Alfreider, Albin; Psenner, Roland; Amann, Rudolf

    1998-01-01

    The seasonal variations in community structure and cell morphology of pelagic procaryotes from a high mountain lake (Gossenköllesee, Austria) were studied by in situ hybridization with rRNA-targeted fluorescently labeled oligonucleotide probes (FISH) and image-analyzed microscopy. Compositional changes and biomass fluctuations within the assemblage were observed both in summer and beneath the winter ice cover and are discussed in the context of physicochemical and biotic parameters. Proteobacteria of the beta subclass (beta-proteobacteria) formed a dominant fraction of the bacterioplankton (annual mean, 24% of the total counts), whereas alpha-proteobacteria were of similar relative importance only during spring (mean, 11%). Bacteria of the Cytophaga-Flavobacterium cluster, although less abundant, constituted the largest fraction of the filamentous morphotypes during most of the year, thus contributing significantly to the total microbial biomass. Successive peaks of threadlike and rod-shaped archaea were observed during autumn thermal mixing and the period of ice cover formation, respectively. A set of oligonucleotide probes targeted to single phylotypes was constructed from 16S rRNA-encoding gene clone sequences. Three distinct populations of uncultivated microbes, affiliated with the alpha- and beta-proteobacteria, were subsequently monitored by FISH. About one-quarter of all of the beta-proteobacteria (range, 6 to 53%) could be assigned to only two phylotypes. The bacterial populations studied were annually recurrent, seasonally variable, and vertically stratified, except during the periods of lake overturn. Their variability clearly exceeded the fluctuations of the total microbial assemblage, suggesting that the apparent stability of total bacterioplankton abundances may mask highly dynamic community fluctuations. PMID:9797280

  8. Paleoecological Investigation of Recent Lake Acidification (PIRLA), 1983--1985

    SciTech Connect

    Charles, D.F.; Whitehead, D.R. )

    1989-10-01

    The Paleoecological Investigation of Recent Lake Acidification'' (PIRLA) project, funded by the Electric Power Research Institute, is a broadly interdisciplinary paleoecological study of recent lake acidification. Approximately ten lakes are being studied in each of four low alkalinity regions in North America that are currently receiving acid deposition. The areas are the Adirondack Mountains (NY), northern New England, northern Great Lakes Region, and northern Florida. Sediment cores are being analyzed for diatom and chrysophyte remains to reconstruct acidification histories, including magnitude, rate, and timing of pH and alkalinity changes. Cores are dated using lead-210 and pollen and charcoal. Other sediment analyses include metals, sulfur, soot, and polycyclic aromatic hydrocarbons (PAH). These provide information on lake acidification histories, and the relative roles of natural acidification processes, watershed disturbance, and atmospheric deposition of strong acids. This interim report contains seven papers representing the status of project research as of March 1985. Results support the hypothesis that diatom and chrysophyte sediment stratigraphies can be used to determine the extent of past variations in the pH levels of lakes.

  9. Lake-specific responses to elevated atmospheric nitrogen deposition in the Colorado Rocky Mountains, U.S.A.

    USGS Publications Warehouse

    Nydick, K.R.; LaFrancois, B.M.; Baron, J.S.; Johnson, B.M.

    2003-01-01

    We explored variability among subalpine lakes sharing very similar climate and atmospheric conditions, but differing in watershed characteristics, hydrology, and food web structure. Special attention was given to nitrogen (N) dynamics because the study area receives some of the highest levels of atmospheric N deposition in the Rocky Mountains. We asked if the effect of regional N deposition would be manifested uniformly among neighboring lakes both in terms of ambient conditions and responses to greater nutrient inputs. Catchment vegetation appeared to be the main determinant of ambient nitrate (NO3), phosphate (PO4), and dissolved organic carbon (DOC) concentrations, although in-lake differences in recycling produced variable and contrasting NH4 levels. Phytoplankton chlorophyll a temporarily responded to early season NO3 peaks in the lakes with rocky watersheds, but chlorophyll means over the ice-free season were remarkably similar among lakes despite differences in both nutrient supply and zooplankton grazing. In most cases, phosphorus was limiting to phytoplankton growth, although the importance of N deficiencies was greater in lakes with forested watersheds and fringing wetlands.

  10. Brooktrout Lake case study: biotic recovery from acid deposition 20 years after the 1990 Clean Air Act Amendments.

    PubMed

    Sutherland, James W; Acker, Frank W; Bloomfield, Jay A; Boylen, Charles W; Charles, Donald F; Daniels, Robert A; Eichler, Lawrence W; Farrell, Jeremy L; Feranec, Robert S; Hare, Matthew P; Kanfoush, Sharon L; Preall, Richard J; Quinn, Scott O; Rowell, H Chandler; Schoch, William F; Shaw, William H; Siegfried, Clifford A; Sullivan, Timothy J; Winkler, David A; Nierzwicki-Bauer, Sandra A

    2015-03-03

    The Adirondack Mountain region is an extensive geographic area (26,305 km(2)) in upstate New York where acid deposition has negatively affected water resources for decades and caused the extirpation of local fish populations. The water quality decline and loss of an established brook trout (Salvelinus fontinalis [Mitchill]) population in Brooktrout Lake were reconstructed from historical information dating back to the late 1880s. Water quality and biotic recovery were documented in Brooktrout Lake in response to reductions of S deposition during the 1980s, 1990s, and 2000s and provided a unique scientific opportunity to re-introduce fish in 2005 and examine their critical role in the recovery of food webs affected by acid deposition. Using C and N isotope analysis of fish collagen and state hatchery feed as well as Bayesian assignment tests of microsatellite genotypes, we document in situ brook trout reproduction, which is the initial phase in the restoration of a preacidification food web structure in Brooktrout Lake. Combined with sulfur dioxide emissions reductions promulgated by the 1990 Clean Air Act Amendments, our results suggest that other acid-affected Adirondack waters could benefit from careful fish re-introduction protocols to initiate the ecosystem reconstruction of important components of food web dimensionality and functionality.

  11. Geochemical affinities of a Late Precambrian basaltic dike, Adirondack Lowlands, Northern New York

    SciTech Connect

    Badger, R.L. . Dept. of Geology)

    1993-03-01

    Late Precambrian rifting and the opening of the Iapetus Ocean basin have produced a series of NE-trending basaltic dikes in the Adirondack Lowlands of New York. Twelve samples were taken from the largest of these dikes, a 14 km long body, in order to study the chemical variability along and across strike and to characterize the source region. The dike consists of an assemblage of plagioclase, Ti-rich clinopyroxene, magnetite/ilmenite and a hydrated phase that was probably olivine. All analyzed samples contain normative olivine, and most contain normative nepheline, indicative of alkalic affinities. Chemical variations are relatively minor, with generally as much variation occurring across strike (max. width 10m) as along strike. SiO[sub 2] varies from 43.9--45.0 wt%; TiO[sub 2]: 4.8--5.1 wt%; P[sub 2]O[sub 5]: 0.8--1.1 wt%; Ni: 55--79 ppm; Sr:P 300--600 ppm; Rb: 35--66 ppm; Y/Nb = 1.1; Zr/Nb = 8. Chondrite normalized REE patterns show strong LREE enrichment. Tectonic discrimination plots (Zr--Ti/100--Y[star]) are indicative of within plate magmatism, and plots of Y/nb vs. Zr/Nb suggest an enriched, OIB-type mantle plume source. Trace element characteristics suggest a genetic correlation with Late Precambrian, rift related magmas of the Ottawa Graben and of the eastern Adirondack Mountains and western Vermont.

  12. Southern California climate, hydrology and vegetation over the past ~96 ka from Baldwin Lake, San Bernardino Mountains, California

    NASA Astrophysics Data System (ADS)

    Glover, K. C.; Kirby, M. E.; Rhodes, E. J.; Silveira, E.; Stevens, L. R.; Lydon, S. E.; Whitaker, A.; MacDonald, G. M.

    2015-12-01

    Continuous paleoclimate records are scarce from terrestrial sites in Southern California beyond the Last Glacial Period (i.e. Marine Isotope Stage 2, MIS 2). Baldwin Lake in the Big Bear Valley, San Bernardino Mountains (SBM), is a playa lake in the ecotone between desert and Mediterranean climate and vegetation. We recovered a 27 m core from the site in 2012, which spans ~96 - 10 ka, based upon radiocarbon dating, infrared stimulated luminescence dating, and orbital tuning. Total organic content, total carbonate content, density, magnetic susceptibility, x-ray fluorescence, and grain size data show a lake system that responded in tandem with Marine Isotope State transitions. After the basin closed during MIS 5b, Baldwin Lake was productive for MIS 5a, then cycled through an inorganic phase to a highly organic lowstand by the end of MIS 4. A stratified lake of rapidly-deposited organic silt prevailed throughout MIS 3, then shifted to an inorganic, slow sedimentation regime during MIS 2. Paleoecological data (charcoal and fossil pollen) suggest that the Valley was most prone to wildfire during climate transitions (e.g. the end of the Last Glacial Maximum, ~21 ka). Forest cover was dominated by pine for much of the basin's history, save for the dry period at the onset of MIS 2, and a greater presence of oak woodland at the beginning of MIS 3. The reduced pine cover and increased sagebrush steppe in early MIS 2 suggests a more arid landscape of sagebrush steppe c. 29 - 25 ka, before reverting to wet conditions by the LGM. Throughout MIS 5a - 2, lake organic content fluctuates in tandem with solar radiation values; a possible link between lake productivity and insolation is currently being explored with biogenic silica (BiSi) analysis. The lake was desiccated by ~10 ka, perhaps driven by increasing insolation rates at the onset of MIS 1.

  13. Deglaciation and postglacial environmental changes in the Teton Mountain Range recorded at Jenny Lake, Grand Teton National Park, WY

    NASA Astrophysics Data System (ADS)

    Larsen, Darren J.; Finkenbinder, Matthew S.; Abbott, Mark B.; Ofstun, Adam R.

    2016-04-01

    Sediments contained in lake basins positioned along the eastern front of the Teton Mountain Range preserve a continuous and datable record of deglaciation and postglacial environmental conditions. Here, we develop a multiproxy glacier and paleoenvironmental record using a combination of seismic reflection data and multiple sediment cores recovered from Jenny Lake and other nearby lakes. Age control of Teton lake sediments is established primarily through radiocarbon dating and supported by the presence of two prominent rhyolitic tephra deposits that are geochemically correlated to the widespread Mazama (∼7.6 ka) and Glacier Peak (∼13.6 ka) tephra layers. Multiple glacier and climate indicators, including sediment accumulation rate, bulk density, clastic sediment concentration and flux, organic matter (concentration, flux, δ13C, δ15N, and C/N ratios), and biogenic silica, track changes in environmental conditions and landscape development. Sediment accumulation at Jenny Lake began centuries prior to 13.8 ka and cores from three lakes demonstrate that Teton glacier extents were greatly reduced by this time. Persistent ice retreat in Cascade Canyon was slowed by an interval of small glacier activity between ∼13.5 and 11.5 ka, prior to the end of glacial lacustrine sedimentation ∼11.5 ka. The transition to non-glacial sediments marks the onset of Holocene conditions at Jenny Lake and reflects a shift toward warmer summers, increased vegetation cover, and landscape stability in the Tetons. We discuss the Teton lake sediment records within the context of other regional studies in an effort to construct a comprehensive overview of deglaciation and postglacial environmental conditions at Grand Teton National Park.

  14. Changes in the chemistry of acidified Adirondack streams from the early 1980s to 2008

    USGS Publications Warehouse

    Lawrence, G.B.; Simonin, H.A.; Baldigo, Barry P.; Roy, K.M.; Capone, S.B.

    2011-01-01

    Lakes in the Adirondack region of New York have partially recovered in response to declining deposition, but information on stream recovery is limited. Here we report results of Adirondack stream monitoring from the early 1980s to 2008. Despite a 50% reduction in atmospheric deposition of sulfur, overall increases in pH of only 0.28 and ANC of 13 μeq L-1 were observed in 12 streams over 23 years, although greater changes did occur in streams with lower initial ANC, as expected. In the North Tributary of Buck Creek with high dissolved organic carbon (DOC) concentrations, SO(4)(2-) concentrations decreased from 1999 to 2008 at a rate of 2.0 μmol L-1 y-1, whereas in the neighboring South Tributary with low DOC concentrations, the decrease was only 0.73 μmol L-1 y-1. Ca2+ leaching decreased in the North Tributary due to the SO(4)(2-) decrease, but this was partially offset by an increase in Ca2+ leaching from increased DOC concentrations.

  15. Acid lake in N.Y. gets relief

    NASA Astrophysics Data System (ADS)

    A pond in the Adirondack Mountains of New York State has received a second soothing dose of baking soda. The 21 tons of sodium bicarbonate should moderate the pond's acidic conditions, lethal to fish and other forms of life.Wolf Pond, 25 miles (40 km) north of Saranac Lake, has developed an extremely low pH (4.5) because of acid rain and the runoff of acidic surface water, combined with very little outflow. The pond was first treated with sodium bicarbonate by t h e New York Department of Environmental Conservation in 1984; afterward the pH rose to about 6.2. Fish stocked by local residents have continued to live in the pond, despite the eventual rebound in its acidity.

  16. Photochemical production of organic matter triplet states in water samples from mountain lakes, located below or above the tree line.

    PubMed

    De Laurentiis, Elisa; Minella, Marco; Maurino, Valter; Minero, Claudio; Brigante, Marcello; Mailhot, Gilles; Vione, Davide

    2012-08-01

    The production of triplet states (T(*)) of chromophoric dissolved organic matter (CDOM), reacting with the probe molecule 2,4,6-trimethylphenol (TMP) was measured upon irradiation of water samples, taken from lakes located in a mountain area (NW Italy) between 1450 and 2750 m above sea level. The lakes are located below or above the tree line and surrounded by different vegetation types (trees, alpine meadows or exposed rocks). The most photoactive samples belonged to lakes below the tree line and their fluorescence spectra and CDOM optical features suggested the presence of a relatively elevated amount of humic (allochthonous) material. The lowest (negligible) photoactivity was found for a lake surrounded by exposed rocks. Its CDOM showed an important autochthonous contribution (due to in-lake productivity) and considerably higher spectral slope compared to the other samples, suggesting low CDOM molecular weight and/or aromaticity. Among the samples, CDOM photoactivity (measured as the rate of TMP-reactive T(*) photoproduction) decreased with changing vegetation type in the order: trees, meadows, rocks. It could be connected with decreasing contribution from catchment runoff and increasing contribution from autochthonous processes and possibly precipitation.

  17. Simulation of Climate Change Effects on Hydropower Lake Inflows in a Mountain Basin, South Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Caruso, B. S.; Newton, S.; King, R.; Zammit, C.

    2015-12-01

    Hydroelectric power is a valuable renewable energy resource and the primary source of electricity in New Zealand, but climate change is predicted to have varying effects on mountain rivers and hydropower in the future due to strong topographic, precipitation, and temperature gradients over space. This study models climate change impacts on river inflows to three headwaters hydropower lakes (Pukaki, Tekapo, and Ohau) in the Upper Waitaki Basin of the central South Island using the TopNet hydrological model based on the 1990s (baseline), 2040s, and 2090s periods. The IPCC 4th assessment report A1B emissions scenario and average temperature and precipitation results of 12 Global Circulation Models with statistical downscaling were used as input to TopNet. Indicators of hydrologic alteration were used to estimate and compare 63 flow metrics across the full flow regime based on TopNet output. Kruskall-Wallis tests were used to evaluate significant differences between metrics among the three periods. Implications for hydropower operations, other water resources management needs, and braided river flows and ecology were also evaluated. Results show that annual and cumulative inflows increase for future climate periods for all three lakes. However, seasonal effects cause flows to generally increase in winter and early spring and decrease slightly in summer due to warmer temperatures with more winter rain and less snow. The number of inflow metrics with statistically significant changes is greatest for Lake Pukaki, with the most glacierized catchment, and least for Lake Ohau. High flows and floods generally increase, and low flows/extreme low flows decrease. Overall these changes may be beneficial for hydropower and some braided river floodplain ecological features, but the seasonal shifts will result in greater flood risk in winter and spring, more drought risk in summer and autumn, and additional challenges managing water volumes in these mountain hydropower lakes.

  18. Geological and geochemical investigations of uranium occurrences in the Arrastre Lake area of the Medicine Bow Mountains, Wyoming

    USGS Publications Warehouse

    Miller, W. Roger; Houston, R.S.; Karlstrom, K.E.; Hopkins, D.M.; Ficklin, W.H.

    1977-01-01

    Metasedimentary rocks of Precambrian X age in and near the Snowy Range wilderness study area of southeastern Wyoming are lithologically and chronologically similar to those on the north shore of Lake Huron in Canada. The rocks in Canada contain major deposits of uranium in quartz-pebble conglomerates near the base of the metasedimentary sequence. Similar conglomerates in the Deep Lake Formation in the Medicine Bow Mountains of southeastern Wyoming are slightly radioactive and may contain deposits of uranium and other valuable heavy metals. During the summer of 1976, a geological and geochemical pilot study was conducted in the vicinity of Arrastre Lake in the Medicine Bow Mountains to determine the most effective exploration methods for evaluating the uranium potential of the Snowy Range wilderness study area. The area around Arrastre Lake was selected because of the presence of a radioactive lens within a quartz-pebble conglomerate of the Deep Lake Formation. The results of the survey indicate possible uranium mineralization in the subsurface rocks of this formation. The radon content of the dilute waters of the area is much higher than can be accounted for by the uranium content of the surface rocks. Two sources for the high content of the radon are possible. In either case, the high values of radon obtained in this study are a positive indication of uranium mineralization in the subsurface rocks. The determination of the radon content of water samples is the recommended geochemical technique for uranium exploration in the area. The determination of uranium in water and in organic-rich bog material is also recommended.

  19. Molecular characterization of the planktonic microorganisms in water of two mountain brackish lakes.

    PubMed

    Zeng, Jun; Deng, Li-Juan; Lou, Kai; Zhang, Tao; Yang, Hong-Mei; Shi, Ying-Wu; Lin, Qing

    2014-06-01

    The prokaryotic diversity in two brackish lakes (Sayram Lake and Chaiwopu Lake) was investigated by constructing bacterial and archaeal clone libraries of 16S rRNA genes. Bacterial clones from Sayram Lake were classified into six phyla (Proteobacteria, Verrucomicrobia, Bacteroidetes, Planctomycetes, Acidobacteria, Actinobacteria). Of these, Proteobacteria and Verrucomicrobia were the most dominant, representing 50.4 and 16.8% of the clone library, respectively. Sequences related to Proteobacteria (58.1%), Cyanobacteria (17.2%), Bacteroidetes (15%), Verrucomicrobia (4.3%), Actinobacteria (3.2%) constituted over 97% of the bacterial clone library from Chaiwopu Lake. In addition, 58.8% (Sayram Lake) and 48% (Chaiwopu Lake) of bacterial clones showed high sequence identity to pure cultures. The composition of Archaea was obviously different between the two lakes. Only the Crenarchaeota phylum was found in the Sayram Lake, whereas Archaeal sequences from Chaiwopu Lake were classified into three phyla: Crenarchaeota (5.8%), Thaumarchaeota (81.2%), and Euryarchaeota (13%). Among the archaeal sequences, 94.2% were highly related to cultivable species of the genus Nitrosopumilus, Methanoculleus, and Methanobacterium. These results showed a high diversity of potential cultivable heterotrophic bacteria in Sayram Lake and Chaiwopu Lake. Chaiwopu Lake was a source of potentially novel, cultivable archaea.

  20. Paleomagnetism of the Middle Proterozoic Electra Lake Gabbro, Needle Mountains, southwestern Colorado

    USGS Publications Warehouse

    Harlan, S.S.; Geissman, J.W.

    1998-01-01

    The Electra Lake Gabbro is a small 1.435 Ga pluton that intrudes 1.7 to 1.6 Ga gneisses and schists of the Needle Mountains in southwestern Colorado. Paleomagnetic samples were collected from the main phases of the gabbro, diabase dikes, granite, and alaskite dikes that cut the gabbro and from a partially melted zone in gneiss along the southern margin of the pluton. Gabbro, diabase, and some melt zone samples have a single-polarity characteristic magnetization of northeast declination (D) and moderate negative inclination (I). Demagnetization behavior and rock magnetic characteristics indicate that the remanence is carried by nearly pure magnetite. After correction for the minor west dip of overlying Paleozoic strata, we obtain a mean direction of D = 32.1??, I = -41.9?? (k = 94, ??95 = 3.3??, N = 21 sites) and a paleomagnetic pole at 21.1?? S, 221.1 ??E, (K= 89, A95 = 3.4??). This pole is similar to poles from the Middle Proterozoic Belt Supergroup but is located at a higher southerly latitude than poles from other 1.47-1.44 Ga plutons from North America, most of which plot at equatorial latitudes. The reason for this discrepancy is not clear but may result from a combination of factors, including unrecognized tilting of the gabbro, the failure of this relatively small pluton to fully average paleosecular variation, and uncertainties in the overall reliability of other 1.5-1.4 Ga poles of the North American apparent polar wander path.

  1. Simulation of growth of Adirondack conifers in relation to global climate change

    SciTech Connect

    Pan, Y.; Raynal, D.J. )

    1993-06-01

    Several conifer species grown in plantations in the southeastern Adirondack mountains of New York were chosen to model tree growth. In the models, annual xylem growth was decomposed into several components that reflect various intrinsic or extrinsic factors. Growth signals indicative of climatic effects were used to construct response functions using both multivariate analysis and Kalman filter methods. Two models were used to simulate tree growth response to future CO[sub 2]-induced climate change projected by GCMs. The comparable results of both models indicate that different conifer species have individualistic growth responses to future climatic change. The response behaviors of trees are affected greatly by local stand conditions. The results suggest possible changes in future growth and distributions of naturally occurring conifers in this region.

  2. Persistence of an unusual pelagic zooplankton assemblage in a clear mountain lake

    USGS Publications Warehouse

    Larson, Gary L.; Hoffman, Robert L.; McIntire, C.D.

    2002-01-01

    The planktonic zooplankton assemblage in Mowich Lake, Mount Rainier National Park (MORA), was composed almost entirely of rotifers in 1966 and 1967. Adult pelagic crustacean taxa were rare. Their paucity was attributed to predation by kokanee salmon (Oncorhynchus nerka), which had been stocked in 1961. During a park-wide survey of 24 lakes in 1988, Mowich Lake was the only one that did not contain at least one planktonic crustacean species. Given the apparent persistence of the unusual pelagic zooplankton assemblage in Mowich Lake, the first objective of this study was to document the interannual variation in the taxonomic structure of the zooplankton assemblages in the lake from 1988 through 1999. A second objective was to determine if it was possible to predict the taxonomic composition of the pelagic crustacean zooplankton assemblage in Mowich Lake prior to the stocking of kokanee salmon. The Mowich Lake zooplankton assemblages in 1988a??1999 were consistent with those in 1966 and 1967. Crustacean taxa were extremely rare, but they included most of the primary taxa collected from 23 MORA lakes surveyed in 1988. Nonetheless, the 1988 collections showed that the September rotifer assemblage in Mowich Lake was similar to 10 of the 24 lakes sampled. Seven of the 10 lakes were dominated by cladocerans, primarily Daphnia rosea and Holopedium gibberum. Therefore, it appeared that either one or both of these species may have numerically dominated the crustacean zooplankton assemblage in the lake prior to 1961.

  3. Persistence of an unusual pelagic zooplankton assemblage in a clear, mountain lake

    USGS Publications Warehouse

    Larson, G.L.; Hoffman, R.L.; David, McIntire C.

    2002-01-01

    The planktonic zooplankton assemblage in Mowich Lake, Mount Rainier National Park (MORA), was composed almost entirely of rotifers in 1966 and 1967. Adult pelagic crustacean taxa were rare. Their paucity was attributed to predation by kokanee salmon (Oncorhynchus nerka), which had been stocked in 1961. During a park-wide survey of 24 lakes in 1988, Mowich Lake was the only one that did not contain at least one planktonic crustacean species. Given the apparent persistence of the unusual pelagic zooplankton assemblage in Mowich Lake, the first objective of this study was to document the interannual variation in the taxonomic structure of the zooplankton assemblages in the lake from 1988 through 1999. A second objective was to determine if it was possible to predict the taxonomic composition of the pelagic crustacean zooplankton assemblage in Mowich Lake prior to the stocking of kokanee salmon. The Mowich Lake zooplankton assemblages in 1988-1999 were consistent with those in 1966 and 1967. Crustacean taxa were extremely rare, but they included most of the primary taxa collected from 23 MORA lakes surveyed in 1988. Nonetheless, the 1988 collections showed that the September rotifer assemblage in Mowich Lake was similar to 10 of the 24 lakes sampled. Seven of the 10 lakes were dominated by cladocerans, primarily Daphnia rosea and Holopedium gibberum. Therefore, it appeared that either one or both of these species may have numerically dominated the crustacean zooplankton assemblage in the lake prior to 1961.

  4. A multiproxy study of Holocene water-depth and environmental changes in Lake St Ana, Eastern Carpathian Mountains, Romania

    NASA Astrophysics Data System (ADS)

    Magyari, E. K.; Buczkó, K.; Braun, M.; Jakab, G.

    2009-04-01

    This study presents the results of a multi-disciplinary investigation carried out on the sediment of a crater lake (Lake Saint Ana, 950 m a.s.l.) from the Eastern Carpathian Mountains. The lake is set in a base-poor volcanic environment with oligotrophic and slightly acidic water. Loss-on-ignition, major and trace element, pollen, plant macrofossil and siliceous algae analyses were used to reconstruct Holocene environmental and water-depth changes. Diatom-based transfer functions were applied to estimate the lake's trophic status and pH, while reconstruction of the water-depth changes was based on the plant macrofossil and diatom records. The lowest Holocene water-depths were found between 9,000 and 7,400 calibrated BP years, when the crater was occupied by Sphagnum-bog and bog-pools. The major trend from 7,400 years BP was a gradual increase, but the basin was still dominated by poor-fen and poor fen-pools. Significant increases in water-depth, and meso/oligotrophic lake conditions were found from 5,350(1), 3,300(2) and 2,700 years BP. Of these, the first two coincided with major terrestrial vegetation changes, namely the establishment of Carpinus betulus on the crater slope (1), and the replacement of the lakeshore Picea abies forest by Fagus sylvatica (2). The chemical record clearly indicated significant soil changes along with the canopy changes (from coniferous to deciduous), that in turn led to increased in-lake productivity and pH. A further increase in water-depth around 2,700 years BP resulted in stable thermal stratification and hypolimnetic anoxia that via P-release further increased in-lake productivity and eventually led to phytoplankton blooms with large populations of Scenedesmus cf. S. brasiliensis. High productivity was depressed by anthropogenic lakeshore forest clearances commencing from ca. 1,000 years BP that led to the re-establishment of Picea abies on the lakeshore and consequent acidification of the lake-water. On the whole, these data

  5. XANES spectroscopy as a tool to trace phosphorus transformation during soil genesis and mountain ecosystem development from lake sediments

    NASA Astrophysics Data System (ADS)

    Giguet-Covex, C.; Poulenard, J.; Chalmin, E.; Arnaud, F.; Rivard, C.; Jenny, J.-P.; Dorioz, J.-M.

    2013-10-01

    The aim of this study is to investigate phosphorus (P) species modifications triggered by soil genesis and mountain ecosystem development after glacial retreat using a lake sediment archive (Lake Anterne, North French Alps). Five lake sediment samples, representative of different stages of soil and ecosystem development, were selected for P speciation analyses. Furthermore, a sequence of current soils from the catchment was analyzed to better constrain our interpretations of the lacustrine archive. Synchrotron techniques (X-ray Fluorescence (XRF) mapping and P K-edge X-ray absorption near edge structure (XANES) spectroscopy) were applied to lake sediments, soils, and standards (mineral and organic) to distinguish between different P species. The results show that soil development during the first millennia of the Holocene triggered increased P species diversity. At the onset of the Holocene, P was present as apatite when rocks and leptosols dominated the catchment. Pedogenic processes then led to apatite dissolution and the formation of large amounts of P on metal/clay-organic complexes. P geochemistry during the main step of soil genesis (early leptosols dominated by apatite, low weathered cambisols with P mainly adsorbed on iron oxides, highly weathered podzols with large amounts of P on Al/Fe/clay organic complexes) is thus clearly recorded in lake sediments. P K-edge XANES spectroscopy is particularly relevant as qualitative method to study P species in soils and lake sediments at high spatial resolution. Such resolution is needed to reveal the diversity of small P particles and like this better characterize the P cycle and improve our understanding of ecosystem evolution.

  6. Holocene record of precipitation seasonality from lake calcite δ18O in the central Rocky Mountains, United States

    USGS Publications Warehouse

    Anderson, Lesleigh

    2011-01-01

    A context for recent hydroclimatic extremes and variability is provided by a ~10 k.y. sediment carbonate oxygen isotope (??18O) record at 5-100 yr resolution from Bison Lake, 3255 m above sea level, in northwestern Colorado (United States). Winter precipitation is the primary water source for the alpine headwater lake in the Upper Colorado River Basin and lake water ??18O measurements reflect seasonal variations in precipitation ??18O. Holocene lake water ??18O variations are inferred from endogenic sedimentary calcite ??18O based on comparisons with historic watershed discharge records and tree-ring reconstructions. Drought periods (i.e., drier winters and/or a more rain-dominated seasonal precipitation balance) generally correspond with higher calcite ??18O values, and vice-versa. Early to middle Holocene ??18O values are higher, implying a rain-dominated seasonal precipitation balance. Lower, more variable ??18O values after ca. 3500 yr ago indicate a snow-dominated but more seasonally variable precipitation balance. The middle to late Holocene ??18O record corresponds with records of El Ni??o Southern Oscillation intensification that supports a teleconnection between Rocky Mountain climate and North Pacific sea-surface temperatures at decade to century time scales. ?? 2011 Geological Society of America.

  7. Biogeochemical responses of two alpine lakes to climate change and atmospheric deposition, Jasper and Banff National Parks, Canadian Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Hobbs, W.; Vinebrooke, R. D.; Wolfe, A. P.

    2012-12-01

    The sensitivity of remote alpine ecosystems to global change has been documented by 20th century changes in climate, glacial recession, and terrestrial and aquatic ecosystems. In many cases the magnitude and dominance of abiotic drivers on recent changes in alpine lakes is often mediated by processes within the hydrologic catchment. Here we present sedimentary records of biogeochemical responses in two alpine lake ecosystems to multiple environmental drivers over the last ~ 500 years in Banff and Jasper National parks. We combine paleoecological measures of primary production (fossil microbial pigments) and diatom community structure with geochemical proxies of reactive N (Nr) deposition to describe the nature and rate of recent ecosystem changes. Curator Lake in Jasper shows a strong diatom response to the limnological effects of climate warming (e.g. thermal stratification), but little evidence of changes in Nr cycling over the last ~500 years. The response of McConnell Lake in Banff to climate change is strongly mediated by glacial activity within the catchment, and changing inputs of Nr. Our findings highlight the range of limnological responses that may be expressed by similar ecosystems subjected to comparable abiotic stressors, while further documenting the magnitude of the ecological footprint associated with recent environmental change in mountain park environments.

  8. Holocene Paleoenvironment of the North-central Great Basin: Preliminary Results from Favre Lake, Northern Ruby Mountains, Nevada

    NASA Astrophysics Data System (ADS)

    Starratt, S.; Wahl, D.; Wan, E.; Anderson, L.; Wanket, J.; Olson, H.; Lloyd-Davies, T.; Kusler, J.

    2009-12-01

    Little is known about Holocene climate variability in north-central Nevada. This study aims to assess changes in watershed vegetation, fire history, lake levels and limnological conditions in order to understand secular to millennial-scale changes in regional climate. Favre Lake (2,899 m a.s.l.; 12 m deep; 7.7 hectares) is a flow-through lake in the northern Ruby Mountains. The primary sources of influent, both of which appear to be intermittent, are Castle Lake (2,989 m a.s.l.) and Liberty Lake (3,077 m a.s.l.). The bedrock of the three lake basins is early Paleozoic marble and Mesozoic granite and metamorphic rocks. Bathymetric maps and temperature, pH, salinity, and conductivity profiles have been generated for Favre Lake. Surface samples and a series of cores were also collected using a modified Livingstone piston corer. The presence of the Mazama ash in the basal sediment (~4 m below the sediment/water interface) indicates the record extends to ~7,700 cal yr B.P. Magnetic susceptibility (MS) and loss-on-ignition data indicate that the sediments in the lowest part of the core contain primary and reworked Mazama ash. About 2,000 years ago CaCO3 increased from 2 to 3% of the inorganic sediment. The upper 25 cm of the core are marked by an increase in MS which may indicate increased erosion due to grazing. Between about 7,700 and 6,000 cal yr B.P. the diatom flora is dominated by a diverse assemblage of benthic species. The remainder of the core is dominated by Fragilaria, suggesting that lake level rose and flooded the shelf that surrounds the depocenter of the lake. This is supported by changes in the abundance of the aquatic fern Isoetes. Pinus and Artemisia dominate the pollen record, followed by subordinate levels of Poaceae, Asteraceae, Amaranthaceae, and Sarcobatus. The late early Holocene (7,700-6,000 cal yr B.P.) is dominated by Pinus which is present in reduced amounts during the middle Holocene (6,000-3,000 cal yr B.P.) and then returns to dominance in

  9. Geometry and kinematics of the eastern Lake Mead fault system in the Virgin Mountains, Nevada and Arizona

    USGS Publications Warehouse

    Beard, Sue; Campagna, David J.; Anderson, R. Ernest

    2010-01-01

    The Lake Mead fault system is a northeast-striking, 130-km-long zone of left-slip in the southeast Great Basin, active from before 16 Ma to Quaternary time. The northeast end of the Lake Mead fault system in the Virgin Mountains of southeast Nevada and northwest Arizona forms a partitioned strain field comprising kinematically linked northeast-striking left-lateral faults, north-striking normal faults, and northwest-striking right-lateral faults. Major faults bound large structural blocks whose internal strain reflects their position within a left step-over of the left-lateral faults. Two north-striking large-displacement normal faults, the Lakeside Mine segment of the South Virgin–White Hills detachment fault and the Piedmont fault, intersect the left step-over from the southwest and northeast, respectively. The left step-over in the Lake Mead fault system therefore corresponds to a right-step in the regional normal fault system.Within the left step-over, displacement transfer between the left-lateral faults and linked normal faults occurs near their junctions, where the left-lateral faults become oblique and normal fault displacement decreases away from the junction. Southward from the center of the step-over in the Virgin Mountains, down-to-the-west normal faults splay northward from left-lateral faults, whereas north and east of the center, down-to-the-east normal faults splay southward from left-lateral faults. Minimum slip is thus in the central part of the left step-over, between east-directed slip to the north and west-directed slip to the south. Attenuation faults parallel or subparallel to bedding cut Lower Paleozoic rocks and are inferred to be early structures that accommodated footwall uplift during the initial stages of extension.Fault-slip data indicate oblique extensional strain within the left step-over in the South Virgin Mountains, manifested as east-west extension; shortening is partitioned between vertical for extension-dominated structural

  10. Sediment delivery and lake dynamics in a Mediterranean mountain watershed: Human-climate interactions during the last millennium (El Tobar Lake record, Iberian Range, Spain).

    PubMed

    Barreiro-Lostres, Fernando; Brown, Erik; Moreno, Ana; Morellón, Mario; Abbott, Mark; Hillman, Aubrey; Giralt, Santiago; Valero-Garcés, Blas

    2015-11-15

    Land degradation and soil erosion are key environmental problems in Mediterranean mountains characterized by a long history of human occupation and a strong variability of hydrological regimes. To assess recent trends and evaluate climatic and anthropogenic impacts in these highly human modified watersheds we apply an historical approach combining lake sediment core multi-proxy analyses and reconstructions of past land uses to El Tobar Lake watershed, located in the Iberian Range (Central Spain). Four main periods of increased sediment delivery have been identified in the 8m long sediment sequence by their depositional and geochemical signatures. They took place around 16th, late 18th, mid 19th and early 20th centuries as a result of large land uses changes such as forest clearing, farming and grazing during periods of increasing population. In this highly human-modified watershed, positive synergies between human impact and humid periods led to increased sediment delivery periods. During the last millennium, the lake depositional and geochemical cycles recovered quickly after each sediment delivery event, showing strong resilience of the lacustrine system to watershed disturbance. Recent changes are characterized by large hydrological affections since 1967 with the construction of a canal from a nearby reservoir and a decreased in anthropic pressure in the watershed as rural areas were abandoned. The increased fresh water influx to the lake has caused large biological changes, leading to stronger meromictic conditions and higher organic matter accumulation while terrigenous inputs have decreased. Degradation processes in Iberian Range watersheds are strongly controlled by anthropic activities (land use changes, soil erosion) but modulated by climate-related hydrological changes (water availability, flood and runoff frequency).

  11. Genetic variation between Schistosoma japonicum lineages from lake and mountainous regions in China revealed by resequencing whole genomes.

    PubMed

    Yin, Mingbo; Liu, Xiao; Xu, Bin; Huang, Jian; Zheng, Qi; Yang, Zhong; Feng, Zheng; Han, Ze-Guang; Hu, Wei

    2016-09-01

    Schistosoma infection is a major cause of morbidity and mortality worldwide. Schistosomiasis japonica is endemic in mainland China along the Yangtze River, typically distributed in two geographical categories of lake and mountainous regions. Study on schistosome genetic diversity is of interest in respect of understanding parasite biology and transmission, and formulating control strategy. Certain genetic variations may be associated with adaptations to different ecological habitats. The aim of this study is to gain insight into Schistosoma japonicum genetic variation, evolutionary origin and associated causes of different geographic lineages through examining homozygous Single Nucleotide Polymorphisms (SNPs) based on resequenced genome data. We collected S. japonicum samples from four sites, three in the lake regions (LR) of mid-east (Guichi and Tonglin in Anhui province, Laogang in Hunan province) and one in mountainous region (MR) (Xichang in Sichuan province) of south-west of China, resequenced their genomes using Next Generation Sequencing (NGS) technology, and made use of the available database of S. japonicum draft genomic sequence as a reference in genome mapping. A total of 14,575 SNPs from 2059 genes were identified in the four lineages. Phylogenetic analysis confirmed significant genetic variation exhibited between the different geographical lineages, and further revealed that the MR Xichang lineage is phylogenetically closer to LR Guich lineage than to other two LR lineages, and the MR lineage might be evolved from LR lineages. More than two thirds of detected SNPs were nonsynonymous; functional annotation of the SNP-containing genes showed that they are involved mainly in biological processes such as signaling and response to stimuli. Notably, unique nonsynonymous SNP variations were detected in 66 genes of MR lineage, inferring possible genetic adaption to mountainous ecological condition.

  12. Chemistry and transport of soluble humic substances in forested watersheds of the Adirondack Park, New York

    USGS Publications Warehouse

    Cronan, C.S.; Aiken, G.R.

    1985-01-01

    Studies were conducted in conjunction with the Integrated Lake-Watershed Acidification Study (ILWAS) to examine the chemistry and leaching patterns of soluble humic substances in forested watersheds of the Adirondack region. During the summer growing season, mean dissolved organic carbon (DOC) concentrations in the ILWAS watersheds ranged from 21-32 mg C l-1 in O/A horizon leachates, from 5-7 mg C l-1 in B horizon leachates, from 2-4 mg C l-1 in groundwater solutions, from 6-8 mg C l-1 in first order streams, from 3-8 mg C l-1 in lake inlets, and from 2-7 mg C l-1 in lake outlets. During the winter, mean DOC concentrations dropped significantly in the upper soil profile. Soil solutions from mixed and coniferous stands contained as much as twice the DOC concentration of lysimeter samples from hardwood stands. Results of DOC fractionation analysis showed that hydrophobia and hydrophilic acids dominate the organic solute composition of natural waters in these watersheds. Charge balance and titration results indicated that the general acid-base characteristics of the dissolved humic mixture in these natural waters can be accounted for by a model organic acid having an averagepKa of 3.85, an average charge density of 4-5 ??eq mg-1 C at ambient pH, and a total of 6-7 meq COOH per gram carbon. ?? 1985.

  13. A new species and new distribution records for Braconidae from Mountain Lake Biological Station in southwestern Virginia and a redescription of Pentapleura foveolata Viereck

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One new species of Alysiinae, Coelinius wrayi Kula, is described. Pentapleura foveolata Viereck, also in Alysiinae and previously known only from a male collected at the type locality in Connecticut, is redescribed based on six females and two males collected at Mountain Lake Biological Station (MLB...

  14. Robust Lake Level Extraction in Mountainous Areas By Retracking Cryosat Sarin Mode Waveforms.

    NASA Astrophysics Data System (ADS)

    Kleinherenbrink, M.; Ditmar, P.; Lindenbergh, R.

    2014-12-01

    Since the beginning of the 1990s, lake levels can be monitored using satellite altimetry.This is notably an advantage for lakes located in remote areas, where no gauges are present.Two disadvantages of traditional satellite altimetry however are the limited number of ground tracks and the pulse limited footprint size.In 2010 Cryosat was launched with onboard a SAR Interferometric Radar ALtimeter (SIRAL), which has a dense ground track spacing of 7-8 km and a along-track resolution of approximately 300 m in the SAR Interferometric (SARIn) mode.This potentially enables Cryosat to sample more lakes and obtain more reliable lake levels in near-shore regions.Still, the accuracy and robustness of standard level 2 data is limited due to pollution of the waveform in near-shore regions.We propose therefore to actively extract the water surface by a novel retracking algorithm based on cross-correlation of observed level 1b waveforms with a generic simulated waveform.As a result, we obtain multiple elevations per waveform.As the water level is contributing to each consecutive waveform over the lake, it can efficiently be extracted using a majority voting scheme.By comparing the lake levels to those obtained with Jason-2 over Lake Nasser an RMS of differences of 0.30 m is found.After this validation step, we applied the procedure to lakes in Tian Shan and Tibet.In these areas 125 lakes are measured at least four times in two years, of which 30 are even sampled ten times in two years and 16 more than twenty times.For the ones sampled more than twenty times an additional slope in the water surface could be estimated, which can be an effect of prevailing winds or errors in the geoid model.Ultimately, we found a negative water balance in the natural lakes in Tian Shan and a positive balance in Tibet between February 2012 and February 2014.These results clearly demonstrate the potential of Cryosat, as previous radar altimetry missions were only able to sample about 70 lakes over

  15. Preliminary surficial geologic map of a Calico Mountains piedmont and part of Coyote Lake, Mojave desert, San Bernardino County, California

    USGS Publications Warehouse

    Dudash, Stephanie L.

    2006-01-01

    This 1:24,000 scale detailed surficial geologic map and digital database of a Calico Mountains piedmont and part of Coyote Lake in south-central California depicts surficial deposits and generalized bedrock units. The mapping is part of a USGS project to investigate the spatial distribution of deposits linked to changes in climate, to provide framework geology for land use management (http://deserts.wr.usgs.gov), to understand the Quaternary tectonic history of the Mojave Desert, and to provide additional information on the history of Lake Manix, of which Coyote Lake is a sub-basin. Mapping is displayed on parts of four USGS 7.5 minute series topographic maps. The map area lies in the central Mojave Desert of California, northeast of Barstow, Calif. and south of Fort Irwin, Calif. and covers 258 sq.km. (99.5 sq.mi.). Geologic deposits in the area consist of Paleozoic metamorphic rocks, Mesozoic plutonic rocks, Miocene volcanic rocks, Pliocene-Pleistocene basin fill, and Quaternary surficial deposits. McCulloh (1960, 1965) conducted bedrock mapping and a generalized version of his maps are compiled into this map. McCulloh's maps contain many bedrock structures within the Calico Mountains that are not shown on the present map. This study resulted in several new findings, including the discovery of previously unrecognized faults, one of which is the Tin Can Alley fault. The north-striking Tin Can Alley fault is part of the Paradise fault zone (Miller and others, 2005), a potentially important feature for studying neo-tectonic strain in the Mojave Desert. Additionally, many Anodonta shells were collected in Coyote Lake lacustrine sediments for radiocarbon dating. Preliminary results support some of Meek's (1999) conclusions on the timing of Mojave River inflow into the Coyote Basin. The database includes information on geologic deposits, samples, and geochronology. The database is distributed in three parts: spatial map-based data, documentation, and printable map

  16. Data-collection methods and quality-assurance/quality-control procedures used in the study of episodic stream acidification and its effect on fish and aquatic invertebrates in four Catskill Mountain streams, New York, 1988-90

    USGS Publications Warehouse

    Ranalli, Anthony J.; Baldigo, Barry P.; Horan-Ross, Debra; Allen, Ronald V.

    1997-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, conducted a 20-month study during 1988-90 to evaluate the effects of episodic acidification on fish and aquatic invertebrates in pristine headwater streams in the Catskill Mountains of New York. The study was part of the Episodic Response Project, a regional survey of episodic acidification by the U.S. Environmental Protection Agency, and was carried out simultaneously with other studies in the Adirondack Mountains of New York by the Adirondack Lake Survey Corporation and in central Pennsylvania by Pennsylvania State University. This report summarizes the methods used, describes the sampling sites, and presents the data collected from October 1, 1988 through May 30, 1990 at four headwater watersheds (Biscuit Brook, East Branch Neversink River, Black Brook, and High Falls Brook). The study entailed (1) monitoring the quantity and chemical quality of atmospheric deposition and the quality of discharge of streams, and (2) experiments to determine the effect of stream-water-quality changes on fish and invertebrate populations.

  17. Dynamic coupling of volcanic CO2 flow and wind at the HorseshoeLake tree kill, Mammoth Mountain, CA

    SciTech Connect

    Lewicki, J.L.; Hilley, G.E.; Tosha, T.; Aoyagi, R.; Yamamoto, K.; Benson, S.M.

    2006-11-20

    We investigate spatio-temporal relationships between soilCO2 flux (FCO2), meteorological variables, and topography over a ten-dayperiod (09/12/2006 to 09/21/2006) at the Horseshoe Lake tree kill,Mammoth Mountain, CA. Total CO2 discharge varied from 16 to 52 t d-1,suggesting a decline in CO2 emissions over decadal timescales. Weobserved systematic changes in FCO2 in space and time in association witha weather front with relatively high wind speeds from the west and lowatmospheric pressures. The largest FCO2 changes were observed inrelatively high elevation areas. The variations in FCO2 may be due todynamic coupling of wind-driven airflow through the subsurface and flowof source CO2 at depth. Our results highlight the influence of weatherfronts on volcanic gas flow in the near-surface environment and how thisinfluence can vary spatially within a study area.

  18. Geochemistry of Springs in a Region Impacted by Natural Leakage of CO2 , Around Mammoth Mountain, Mammoth Lakes, Ca

    NASA Astrophysics Data System (ADS)

    Raskin, S.; Ellis, A. S.; Khachikian, C.; Luna, J.

    2012-12-01

    Carbon sequestration—the practice of injecting CO2 into geologic reservoirs—is a potentially effective but inadequately understood greenhouse gas mitigation method. Little is known about the impacts of CO2 on surrounding environments should reservoir leakage occur. Magma chambers beneath Mammoth Mountain, Ca, release large volumes of CO2 into the mountain's soil and water, simulating a leaking CO2 reservoir. This study examines the chemistry of springs at Mammoth Mountain in order to provide insights into the impact of elevated CO2 on water chemistry. Evans (2002) confirmed the presence of dissolved CO2 in Mammoth springs at concentrations ranging from 13.8 to 27.8 mmol/L. We hypothesize that waters will be moderately acidified by the CO2+H2O > H2CO3 reaction. Acidified waters may weather the native geology more efficiently than non-acidified waters. We analyzed and collected in-situ data and water samples from Mammoth Mountain springs on four trips during the summers of 2011 and 2012. These high elevations springs feature water temperatures ranging from 3.6 to 15.0 oC, pH values ranging from 5.36-8.26, and conductivities from 9.5-441 (μS/cm). Water emitted at low conductivity, dilute springs is likely sourced from recent snowmelt and has a smaller groundwater component. Low pH value springs are clustered on Mammoth Mountain's southwest flank. Water isotopes and major ions were analyzed to gain further insight into processes influencing these springs. Hydrogen and oxygen isotopes in spring waters conform to the global meteoric water line with δ18O ranging from -14.7 to -16.0‰ and δD ranging from -119.5 to -107.2‰. Isotopic signatures of springs farther east are progressively lighter, suggesting that springs are fed by local precipitation. Major ion analysis shows that spring's water chemistries generally fit along mixing lines between the major rhyolite, andesite, and basalt species that compose Mammoth. Springs on Mammoth's western flank, near the

  19. Holocene and latest Pleistocene oblique dextral faulting on the southern Inyo Mountains fault, Owens Lake basin, California

    USGS Publications Warehouse

    Bacon, S.N.; Jayko, A.S.; McGeehin, J.P.

    2005-01-01

    The Inyo Mountains fault (IMF) is a more or less continuous range-front fault system, with discontinuous late Quaternary activity, at the western base of the Inyo Mountains in Owens Valley, California. The southern section of the IMF trends ???N20??-40?? W for at least 12 km at the base of and within the range front near Keeler in Owens Lake basin. The southern IMF cuts across a relict early Pliocene alluvial fan complex, which has formed shutter ridges and northeast-facing scarps, and which has dextrally offset, well-developed drainages indicating long-term activity. Numerous fault scarps along the mapped trace are northeast-facing, mountain-side down, and developed in both bedrock and younger alluvium, indicating latest Quaternary activity. Latest Quaternary multiple- and single-event scarps that cut alluvium range in height from 0.5 to 3.0 m. The penultimate event on the southern IMF is bracketed between 13,310 and 10,590 cal years B.P., based on radiocarbon dates from faulted alluvium and fissure-fill stratigraphy exposed in a natural wash cut. Evidence of the most recent event is found at many sites along the mapped fault, and, in particular, is seen in an ???0.5-m northeast-facing scarp and several right-stepping en echelon ???0.5-m-deep depressions that pond fine sediment on a younger than 13,310 cal years B.P. alluvial fan. A channel that crosses transverse to this scarp is dextrally offset 2.3 ?? 0.8 m, providing a poorly constrained oblique slip rate of 0.1-0. 3 m/ k.y. The identified tectonic geomorphology and sense of displacement demonstrate that the southern IMF accommodates predominately dextral slip and should be integrated into kinematic fault models of strain distribution in Owens Valley.

  20. Mid-late Holocene climate and vegetation in northeastern part of the Altai Mountains recorded in Lake Teletskoye

    NASA Astrophysics Data System (ADS)

    Rudaya, Natalia; Nazarova, Larisa; Novenko, Elena; Babich, Valery; Kalugin, Ivan; Daryin, Andrei

    2015-04-01

    We report the first high-resolution (with intervals ca. 20-50 years) late-Holocene (4200 yr BP) pollen record from Lake Teletskoye, Altai Mountains, obtained from the underwater Ridge of Sofia Lepneva in 2006 (core Tel 2006). The study presents (i) the results of palynological analysis of Tel 2006; (ii) the results of spectral analysis of natural cycles based on the periodical fluctuation of taiga-biome curve; and (iii) quantitative reconstructions of the late-Holocene regional vegetation, woody coverage and climate in northern part of the Altai Mountains in order to define place of Northeast Altai on the map of the late-Holocene Central Asian environmental history. Late Holocene vegetation of the northeastern part of Altai recorded in Tel 2006 core is characterized by spread of dark-coniferous forest with structure similar to modern. Dominant trees, Siberian pine (Pinus sibirica) and Siberian fir (Abies sibirica), are the most ecological sensitive taxa between Siberian conifers (Shumilova, 1962), that as a whole suggests mild and humid climatic conditions during last 4200 years. However, changes of pollen taxa percentages and results of numerical analysis reveal pronounced fluctuation of climate and vegetation. Relatively cool and dry stage occurred prior to ca. 3500 cal yr BP. Open vegetation was widespread in the region with maximum deforestation and minimal July temperatures between 3800-3500 cal yr BP. Steppe-like communities with Artemisia, Chenopodiaceae and Cyperaceae could grow on the open sites around Lake Teletskoye. Reconstructed woody coverage is very low and varies between 29-35%. After ca. 3500 cal yr BP the area of dark-coniferous mountain taiga has significantly enlarged with maximums of woody coverages and taiga biome scores between ca. 2470-1040 cal yr BP. In the period of ~3500-2500 cal yr BP the averages July temperatures increased more than 1 0C. Climate became warmer and wetter. During last millennium (after 1040 cal yr BP) average July

  1. Long-term trends in breeding birds in an old-growth Adirondack forest and the surrounding region

    USGS Publications Warehouse

    McNulty, S.A.; Droege, S.; Masters, R.D.

    2008-01-01

    Breeding bird populations were sampled between 1954 and 1963, and 1990 and 2000 in an old-growth forest, the Natural Area of Huntington Wildlife Forest (HWF), in the Adirondack Mountains of New York. Trends were compared with data from regional North American Breeding Bird Surveys (BBS) and from a forest plot at Hubbard Brook Experimental Forest, New Hampshire. Trends for 22 species in the HWF Natural Area were negative, eight were positive, and one was zero; 20 were significant. Fifteen of 17 long-distance migrants declined, whereas 7 of 14 short-distance migrants and permanent residents declined. Most (74%) HWF Natural Area species, despite differences in sampling periods and local habitat features, matched in sign of trend when compared to Adirondack BBS routes, 61% matched northeastern BBS routes, and 71% matched eastern United States BBS routes, while 66% matched Hubbard Brook species. The agreement in population trends suggests that forest interior birds, especially long-distance migrants, are affected more by regional than local factors. The analysis indicated that bird trends generated from BBS routes may not be as biased toward roads as previously suggested.

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

    SciTech Connect

    Pair, D.L. . Dept. of Geology)

    1993-03-01

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

  3. Precipitation variability in High Mountain Asia from multiple datasets and implication for water balance analysis in large lake basins

    NASA Astrophysics Data System (ADS)

    Song, Chunqiao; Huang, Bo; Ke, Linghong; Ye, Qinghua

    2016-10-01

    For the period 1979-2011, eight gridded monthly precipitation datasets, including GPCP, CMAP-1/2, TRMM, PREC/L, APHRODITE, NCEP-2 and ERA-Interim, are inter-compared with each other and station observations over High Mountain Asia (HMA). The precipitation variability from the first six gauge-based or merged analysis datasets agree better with each other than with the two reanalysis data. The long-term trend analysis of GPCP, CMAP-1, PREC/L and APHRODITE precipitation datasets consistently reveals moderate increases in the inner and northeastern Tibetan Plateau (TP) and northwest Xinjiang, and obvious decreases in the southeast TP. However, in the Himalayas and Karakorum, there are large discrepancies among different datasets, where GPCP and APHRODITE precipitation datasets show significant decreases along the Himalayas while other datasets show strong spatial heterogeneity or slight variations. The larger uncertainties in the rugged area may be largely attributed to scarce station observations, as well as the stronger snow-induced scattering by microwave measurement. To assess which precipitation datasets tend to be more suitable for hydrologic analysis in HMA, we further investigate the accuracy of precipitation estimates at basin scale by comparing with gauge-based observations, and examine the coherences of annual lake water budgets and precipitation variability over four large closed lake catchments. The results indicate that two reanalysis precipitation datasets show evidently weaker correlations with station observations; the other six datasets perform better in indicating inter-annual variations of lake water budgets. It suggests that these merged analysis precipitation datasets, especially for GPCP, CMAP-1/2 and PREC/L, have the potential in examining regional water balances of the inner basins in HMA.

  4. Reconstruction of Holocene Temperature History in the Rwenzori Mountains (uganda - DR Congo) Based on Midge Analysis of Lake Sediments

    NASA Astrophysics Data System (ADS)

    Eggermont, H.; Audenaert, L.; Russell, J. M.; Verschuren, D.

    2011-12-01

    The Rwenzori Mountains (Uganda-DR Congo) are still one of the most glaciated areas in tropical Africa, but permanent ice will probably disappear entirely in the next few decades. Post-glacial retreat of the Rwenzori glaciers has created numerous lakes, which are hydrologically and ecologically sensitive to climate warming. Sediments accumulating on the bottom of these lakes chronicle the history of central African climate and environmental dynamics, and thus provide the long-term perspective needed to predict the impacts of future climate change on these unique tropical cold-water ecosystems and their biota. In this context, we studied the sediment record of Lake Upper Kachope at ~3960 m elevation, which roughly spans the last 9000 years, and used fossil chironomid remains (Insecta: Diptera) to reconstruct Holocene temperature changes at high elevation in the Rwenzori. Taking into account a probable mid-Holocene hiatus, the obtained temperature reconstruction shows a clear long-term trend in Holocene temperature variation, but with a modest amplitude of ~2-3 °C. From the early to the mid-Holocene, there is a marked shift from species with a lower to species with a higher temperature optimum. In the last few millennia there is a return of chironomid species with colder optima, with century-scale variation that may reflect temperature fluctuation during the Medieval Climate Anomaly and Little Ice Age. Inferences from the very top of the cored section clearly reflect a warming trend over the past century. These data suggest that today's Rwenzori glaciers have existed for the last ~2000 years, but may have been lacking during much of the mid- to late-Holocene.

  5. Magmatic processes that generated the rhyolite of Glass Mountain, Medicine Lake volcano, N. California

    USGS Publications Warehouse

    Grove, T.L.; Donnelly-Nolan, J. M.; Housh, T.

    1997-01-01

    Glass Mountain consists of a 1 km3, compositionally zoned rhyolite to dacite glass flow containing magmatic inclusions and xenoliths of underlying shallow crust. Mixing of magmas produced by fractional crystallization of andesite and crustal melting generated the rhyolite of Glass Mountain. Melting experiments were carried out on basaltic andesite and andesite magmatic inclusions at 100, 150 and 200 MPa, H2O-saturated with oxygen fugacity controlled at the nickel-nickel oxide buffer to provide evidence of the role of fractional crystallization in the origin of the rhyolite of Glass Mountain. Isotopic evidence indicates that the crustal component assimilated at Glass Mountain constitutes at least 55 to 60% of the mass of erupted rhyolite. A large volume of mafic andesite (2 to 2.5 km3) periodically replenished the magma reservoir(s) beneath Glass Mountain, underwent extensive fractional crystallization and provided the heat necessary to melt the crust. The crystalline residues of fractionation as well as residual liquids expelled from the cumulate residues are preserved as magmatic inclusions and indicate that this fractionation process occurred at two distinct depths. The presence and composition of amphibole in magmatic inclusions preserve evidence for crystallization of the andesite at pressures of at least 200 MPa (6 km depth) under near H2O-saturated conditions. Mineralogical evidence preserved in olivine-plagioclase and olivine-plagioclase-high-Ca clinopyroxene-bearing magmatic inclusions indicates that crystallization under near H2O-saturated conditions also occurred at pressures of 100 MPa (3 km depth) or less. Petrologic, isotopic and geochemical evidence indicate that the andesite underwent fractional crystallization to form the differentiated melts but had no chemical interaction with the melted crustal component. Heat released by the fractionation process was responsible for heating and melting the crust.

  6. Holocene environmental changes inferred from biological and sedimentological proxies in a high elevation Great Basin lake in the northern Ruby Mountains, Nevada, USA

    USGS Publications Warehouse

    Wahl, David B.; Starratt, Scott W.; Anderson, Lysanna; Kusler, Jennifer E.; Fuller, Christopher C.; Addison, Jason A.; Wan, Elmira

    2015-01-01

    Multi-proxy analyses were conducted on a sediment core from Favre Lake, a high elevation cirque lake in the northern Ruby Mountains, Nevada, and provide a ca. 7600 year record of local and regional environmental change. Data indicate that lake levels were lower from 7600-5750 cal yr BP, when local climate was warmer and/or drier than today. Effective moisture increased after 5750 cal yr BP and remained relatively wet, and possibly cooler, until ca. 3750 cal yr BP. Results indicate generally dry conditions but also enhanced climatic variability from 3750-1750 cal yr BP, after which effective moisture increased. The timing of major changes in the Favre Lake proxy data are roughly coeval and in phase with those recorded in several paleoclimate studies across the Great Basin, suggesting regional climatic controls on local conditions and similar responses at high and low altitudes.

  7. Coherent late-Holocene climate-driven shifts in the structure of three Rocky Mountain lakes

    USGS Publications Warehouse

    Stone, Jeffery R.; Saros, Jasmine E.; Pederson, Gregory T.

    2016-01-01

    Large-scale atmospheric pressure centers, such as the Aleutian and Icelandic Low, have a demonstrated relationship with physical lake characteristics in contemporary monitoring studies, but the responses to these phenomena are rarely observed in lake records. We observe coherent changes in the stratification patterns of three deep (>30 m) lakes inferred from fossil diatom assemblages as a response to shifts in the location and intensity of the Aleutian Low and compare these changes with similar long-term changes observed in the δ18O record from the Yukon. Specifically, these records indicate that between 3.2 and 1.4 ka, the Aleutian Low shifted westward, resulting in an increased frequency of storm tracks across the Pacific Northwest during winter and spring. This change in atmospheric circulation ultimately produced deeper mixing in the upper waters of these three lake systems. Enhanced stratification between 4.5 and 3.3 ka and from 1.3 ka to present suggests a strengthened Aleutian Low and more meridional circulation.

  8. Recent decadal glacier mass balances over the Western Nyainqentanglha Mountains and the increase in their melting contribution to Nam Co Lake measured by differential bistatic SAR interferometry

    NASA Astrophysics Data System (ADS)

    Li, Gang; Lin, Hui

    2017-02-01

    The Western Nyainqentanglha Mountains locates in the southeastern center of the Inner Tibetan Plateau (ITP). Glaciers in this region are influenced by both the continental climate of Central Asia and the Indian Monsoon system. Their melting on the western slopes feeds the Nam Co Lake, which is the second largest endorheic lake in the ITP. The elevation of Nam Co Lake increased at a rate of 0.25 ± 0.12 m year- 1 from 2003 to 2009. In this study, aimed at quantifying the decadal glacier mass balance in the Western Nyainqentanglha Mountains and their increasing melting contribution to Nam Co Lake; we applied the differential Bistatic SAR interferometry method to five pairs of TanDEM CoSSC datasets observed between 2013 and 2014 and SRTM acquired in 2000. The mean annual mass loss rate was - 0.235 ± 0.127 m w.e. year- 1 for the entire range. The mass loss rate for the northwestern slope (inside the Nam Co Lake drainage basin) and the southeastern slope (outside the Nam Co Lake drainage basin) were - 0.268 ± 0.129 m w.e. year- 1 and ¬ 0.219 ± 0.126 m w.e. year- 1, respectively. Our results agree well with previous fieldwork at the Zhadang and Gurenhekou glaciers located on the northwestern and southeastern slopes. Debris-cover suppressed glacier downwasting to some extent. By presuming that all of the melted ice flows into the lake, the glaciers' melting contribution to Nam Co Lake's increasing water volume was approximately 10.50 ± 9.00% during the period between 2003 and 2009.

  9. Snow-extent mapping and lake ice studies using ERTS-1 MSS together with NOAA-2 VHRR. [Lake Ontario-Lake Erie Basins and Sierra Nevada Mountains, California

    NASA Technical Reports Server (NTRS)

    Wiesnet, D. R.; Mcginnis, D. F.

    1974-01-01

    Five snow extent maps of the 5,601 sq km American River Basin were prepared using a Zoom Transfer Scope from ERTS-1 MSS band 4 imagery. The maps were generally completed within one hour. A snowmelt curve based on ERTS-1 imagery was used as a calibration standard or comparison for maps prepared from NOAA-2 VHRR imagery in the same manner. Cost comparisons with U-2 derived imagery indicate that ERTS-1 snow mapping of the basins is six times faster. Conservative estimates of comparable aircraft snow survey flights yields a cost figure 200 times that of the ERTS-1 snow map. Snow mapping attempts in the Lake Ontario Basin demonstrated that ERTS-1 is not well suited to large basins. Optimum size of basins for ERTS studies is believed to range from about 250 sq km to 30,000 sq km. The value of the ERTS-1 MSS for Great Lake ice evaluation was proved during the past winter on Lake Erie. Not only were ice features and types of ice identified, but melting ice was detected through the combined use of band 5 and band 7. Ice movement (direction and speed) was mapped by examining imagery from two successive days.

  10. Mineral resources of the Diablo Mountain Wilderness Study Area, Lake County, Oregon

    SciTech Connect

    Diggles, M.F.; King, H.D.; Gettings, ME.; Conrad, J.E.; Sawatzky, D.L.; Soreghan, G.S.

    1990-01-01

    This paper reports on the Diablo Mountain Wilderness Study Area which has no identified mineral resources, but it has moderate mineral resource potential for soda ash, boron compounds, sodium sulfate, magnesium compounds, salts, potash, bromine, lithium, tungsten, and geothermal energy. The area also has low mineral resource potential for low-grade, high-tonnage, epithermal, hot-spring gold-silver deposits, for magnesium deposits, and for oil and gas.

  11. Description of a new species of Niphargus (Crustacea: Amphipoda: Niphargidae): the first record of a lake ecomorph in the Carpathian Mountains.

    PubMed

    Petković, Matija; Delić, Teo; Lučić, Luka; Fišer, Cene

    2015-10-01

    We describe and phylogenetically characterize a new species Niphargus mirocensis from Mt. Miroč, eastern Serbia. This species shows distinct morphology typical for a lake ecomorph of niphargid amphipod, i.e. large and stout body, elongated appendages and raptorial gnathopods and presents the first record of this ecomorph in Carpathian Mountains. Phylogenetic analyses based on Cytochrome Oxidase Subunit 1 gene (COI), Histone (H3) and 28S rRNA (28S) suggests that species is nested within a clade of lake ecomorphs spread in Italy and Central Dinaric Region. The new finding is geographic extension of clade's range, the species of which are generally narrow endemics.

  12. Connections Between Cold Air Pools and Mountain Valley Fog Events in Salt Lake City

    NASA Astrophysics Data System (ADS)

    Chachere, Catherine N.; Pu, Zhaoxia

    2016-09-01

    The aim of this study is to investigate the connection between cold air pools and fog events in Salt Lake City, Utah, United States. Statistical analyses are conducted using soundings and reported automated surface observing system data from Salt Lake International Airport for the last eighteen cold seasons (October to March, during 1997-2015). A Chi-square test of independence is performed on identified cold air pool, and fog events to determine whether the two events are correlated. Conditional probabilities are then computed to investigate the occurrence of fog, given the presence of a cold pool. These probabilities are compared against that of random fog generation in the mid-winter. It is concluded that the dependence between cold air pools and fog events is statistically significant. The presence of a cold pool makes the formation of fog more likely than random generation.

  13. Late Pleistocene and Holocene paleolimnology of two mountain lakes in western Tasmania.

    USGS Publications Warehouse

    Platt, Bradbury J.

    1986-01-01

    The analysis of diatoms from two lake-sediment cores from southwestern Tasmania that span the Pleistocene-Holocene boundary provides insight about paleolimnological and paleoclimatic change in this region. Both Lake Vera and Eagle Tarn have lacustrine records that begin about 12 000 yr ago. Both lakes have had similar limnological histories. Each appears to have been larger and more alkaline 12 000 yr ago and both became shallower through time. Fossil diatom assemblages about 11 000 yr old indicate shallow- water environments that fluctuated in pH, and between dilute and possibly slightly saline hydrochemical conditions. Beginning 11 500 yr ago, limnological conditions of shallow, dilute water of neutral pH prevailed, indicating reduction of moisture stress. A subsequent transition to diatom assemblages indicative of acidic conditions about 10 000 yr ago parallels the establishment of rain-forest vegetation and essentially modern climatic conditions with excess precipitation over evaporation. Changes at these separate and distinctive sites suggests a regional paleoclimatic cause rather than local environmental effects. Latest Pleistocene climates were apparently more continental and drier than Holocene climates in southwestern Tasmania.-from Author

  14. The bacterial community composition of the surface microlayer in a high mountain lake

    PubMed Central

    Hörtnagl, Paul; Pérez, Maria Teresa; Zeder, Michael; Sommaruga, Ruben

    2010-01-01

    The existence of bacterioneuston in aquatic ecosystems is well established, but little is known about its composition and dynamics, particularly in lakes. The bacterioneuston underlies extreme conditions at the air–water boundary, which may influence its dynamics in a different way compared with the bacterioplankton. In this study, we assessed quantitative changes in major bacterial groups of the surface microlayer (SML) (upper 900 μm) and the underlying water (ULW) (0.2–0.5 m depth) of an alpine lake during two consecutive ice-free seasons. Analysis of the bacterial community composition was done using catalyzed reporter deposition FISH with oligonucleotide probes. In addition, several physicochemical parameters were measured to characterize these two water layers. Dissolved organic carbon was consistently enriched in the SML and the dissolved organic matter pool presented clear signals of photodegradation and photobleaching. The water temperature was generally colder in the SML than in the subsurface. The bacterial community of the SML and the ULW was dominated by Betaproteobacteria and Actinobacteria. The bacterial community composition was associated with different combinations of physicochemical factors in these two layers, but temporal changes showed similar trends in both layers over the two seasons. Our results identify the SML of alpine lakes as a microhabitat where specific bacterial members such as of Betaproteobacteria seem to be efficient colonizers. PMID:20528985

  15. Hydrogeologic Framework Development for Integrated Hydrologic Modeling of Mountain Block Alluvial Systems in Lake Tahoe and Martis Valley, Nevada and California

    NASA Astrophysics Data System (ADS)

    Gardner, M.; Huntington, J. L.; Niswonger, R. G.; Reeves, M.; Pohll, G. M.

    2012-12-01

    The U.S. Department of Interior has identified the Truckee River basin as highly likely for potential water supply crises and conflict in the next 15 years. A critical water supply to the Truckee River is outflow from Lake Tahoe and watershed contributions from Martis Valley. This project utilizes an integrated surface and groundwater model, GSFLOW, in the Lake Tahoe and Martis Valley basins to assess the effects of climate on surface and groundwater interactions and to identify hydrologic mechanisms responsible for changes in groundwater levels, summer baseflows, spring flows, soil moisture, and lake levels. Maintaining a balance between hydrostratigraphic resolution and grid discretization is a key objective in developing realistic and computationally efficient integrated surface and groundwater models. This is particularly difficult in mountainous regions with complex topography where low permeability mountain block is overlain by thin, higher permeability alluvium and glacial deposits near stream channels. In this work, we outline a novel approach used to develop grid-based hydrogeologic conceptualizations of the Lake Tahoe and Martis Valley hydrologic basins. This approach employs deductive reasoning and a combination of data-driven automated and manual interpolation conditioned to observe lithologies, cross sectional and surficial geologic maps, and geophysical surveys. This conceptual-hydrogeological framework model, which merges data-driven hydrostratigraphic interpolation with conceptual understanding of the sub-surface system, is essential for constructing integrated models in data limited mountain block regions. Particular emphasis is placed on how maintaining continuity between mountain block, alluvial, and basin fill units through layer configuration and assignment of permeability contrasts markedly improves model performance and efficiency.

  16. Ball Mountain Lake, Jamaica, Vermont. Master Plan for Recreation Resources Development.

    DTIC Science & Technology

    1977-12-01

    Project Structures The dam is a rolled earth and rockfill structure 915 feet in length with a maximum height of 265 feet above the stream bed. The top of...the new road right-of-way. 11 9. Type, Location and Extent of Earth Borrow A large borrow area is located off the access to Ball Mountain Dam . Trees...two Corps of Engineers flood control dams and six other public recreation areas. However, only seven of these areas provide ;winmning and only six

  17. Hydrochemistry dynamics in remote mountain lakes and its relation to catchment and atmospheric features: the case study of Sabocos Tarn, Pyrenees.

    PubMed

    Santolaria, Zoe; Arruebo, Tomas; Urieta, José Santiago; Lanaja, Francisco Javier; Pardo, Alfonso; Matesanz, José; Rodriguez-Casals, Carlos

    2015-01-01

    Increasing the understanding of high mountain lake dynamics is essential to use these remote aquatic ecosystems as proxies of global environmental changes. With this aim, at Sabocos, a Pyrenean cirque glacial lake or tarn, this study shows the main results of a morphological and catchment characterization, along with statistical analyses of its hydrochemical trends and their concomitant driving factors from 2010 to 2013. Dissolved oxygen, water temperature stratification, and its snow and ice cover composition and dynamics have been also investigated. According to morphological analyses, Sabocos can be classified as a medium-large and deep lake, having a circular contour and a long water retention time as compared to Pyrenean glacial lake average values. Sabocos hydrochemistry is mainly determined by very high alkalinity, pH and conductivity levels, and high Ca(2+), Mg(2+), and SO4(2-) content, coming from the easily weatherable limestone-dolomite bedrock. Thus, lake water is well buffered, and therefore, Sabocos tarn is non-sensitive to acidification processes. On the other hand, the main source of K(+), Na(+), and Cl(-) (sea salts) and nutrients (NH4(+), NO3(-), and phosphorous) to lake water appears to be atmospheric deposition. Primary production is phosphorous limited, and due to the N-saturation stage of the poorly developed soils of Sabocos catchment, NO3(-) is the chief component in the total nitrogen pool. External temperature seems to be the major driver regulating lake productivity, since warm temperatures boot primary production. Although precipitation might also play an important role in lake dynamics, especially regarding to those parameters influenced by the weathering of the bedrock, its influence cannot be easily assessed due to the seasonal isolation produced by the ice cover. Also, as occurs in the whole Pyrenean lake district, chemical composition of bulk deposition is highly variable due to the contribution of air masses with different origin.

  18. Sediment records of highly variable mercury inputs to mountain lakes in Patagonia during the past millennium

    NASA Astrophysics Data System (ADS)

    Ribeiro Guevara, S.; Meili, M.; Rizzo, A.; Daga, R.; Arribére, M.

    2010-04-01

    High Hg levels in the pristine lacustrine ecosystems of the Nahuel Huapi National Park, a protected zone situated in the Andes of Northern Patagonia, Argentina, have initiated further investigations on Hg cycling and source identification. Here we report Hg records in sedimentary sequences to identify atmospheric sources during the past millennium. In addition to global transport and deposition, a potential atmospheric Hg source to be considered is the local emissions associated with volcanic activity, because the Park is situated in the Southern Volcanic Zone. Two sediment cores were extracted from Lake Tonček, a small, high-altitude system reflecting mainly direct inputs associated with atmospheric contributions, and Lake Moreno Oeste, a much larger and deeper lake having an extended watershed covered mostly by native forest. The sedimentary sequences were dated based on both 210Pb and 137Cs profiles. In addition, tephra layers were identified and geochemically characterized for chronological application and to investigate any association of volcanic eruptions with Hg records. Hg concentrations in sediments were measured along with 32 other elements, as well as organic matter, subfossil chironomids, and biogenic silica. Observed background Hg concentrations, determined from the sequence domains with lower values, ranged from 50 to 100 ng g-1 dry weight (DW), whereas the surficial layers reached 200 to 500 ng g-1 DW. In addition to this traditional pattern, however, two deep domains in both sequences showed dramatically increased Hg levels reaching 400 to 650 ng g-1 DW; the upper dated to the 18th to 19th centuries, and the lower around the 13th century. These concentrations are not only elevated in the present profiles but also many-fold above the background values determined in other fresh water sediments, as were also the Hg fluxes, reaching 120 to 150 μg m-2 y-1 in Lake Tonček . No correlation was observed between Hg concentrations and the contents of

  19. Sediment records of highly variable mercury inputs to mountain lakes in Patagonia during the past millennium

    NASA Astrophysics Data System (ADS)

    Ribeiro Guevara, S.; Meili, M.; Rizzo, A.; Daga, R.; Arribére, M.

    2009-12-01

    High Hg levels in the pristine lacustrine ecosystems of the Nahuel Huapi National Park, a protected zone situated in the Andes of Northern Patagonia, Argentina, have initiated further investigations on Hg cycling and source identification. Here we report Hg records in sedimentary sequences aiming at identifying atmospheric sources during the past millennium. In addition to global transport and deposition, a potential atmospheric Hg source to be considered is the local emissions associated with volcanic activity, considering that the Park is situated in the Southern Volcanic Zone. Two sediment cores were extracted from Lake Tonček, a small, high-altitude system reflecting mainly direct inputs associated with atmospheric contributions, and Lake Moreno Oeste, a much larger and deeper lake having an extended watershed covered mostly by native forest. The sedimentary sequences were dated based on both 210Pb and 137Cs profiles. In addition, tephra layers were identified and geochemically characterized for chronological application and to investigate any association of volcanic eruptions with Hg records. Hg concentrations in sediments were measured along with 32 other elements, as well as organic matter, fossil chironomids, and biogenic silica. Observed background Hg concentrations, determined from the sequence domains with lower values, ranged from 50 to 100 ng g-1 DW (dry weight), whereas the surficial layers reached 200 to 500 ng g-1 DW. In addition to this traditional pattern, however, two deep domains in both sequences showed dramatically increased Hg levels reaching 400 to 650 ng g-1 DW; the upper dated to the 18th to 19th centuries, and the lower around the 13th century. These concentrations are not only elevated in the present profiles but also many-fold above the background values determined in other fresh water sediments, as were also the Hg fluxes, reaching 120 to 150 μg m-2 y-1 in Lake Tonček. No correlation was observed between Hg concentrations and the

  20. Lake

    ERIC Educational Resources Information Center

    Wien, Carol Anne

    2008-01-01

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

  1. Mountain Island Lake, North Carolina; analysis of ambient conditions and simulation of hydrodynamics, constituent transport, and water-quality characteristics, 1996-97

    USGS Publications Warehouse

    Bales, Jerad D.; Sarver, Kathleen M.; Giorgino, Mary J.

    2001-01-01

    Mountain Island Lake is an impoundment of the Catawba River in North Carolina and supplies drinking water to more than 600,000 people in Charlotte, Gastonia, Mount Holly, and several other communities. The U.S. Geological Survey, in cooperation with the Charlotte-Mecklenburg Utilities, conducted an investigation of the reservoir to characterize hydrologic and water-quality conditions and to develop and apply a simulation model to predict the response of the reservoir to changes in constituent loadings or the flow regime. During 1996-97, flows into Mountain Island Lake were dominated by releases from Cowans Ford Dam on Lake Norman, with more than 85 percent of the total inflow to the reservoir coming from Lake Norman. Riverbend Steam Station discharges accounted for about 12 percent of the inflows to the reservoir, and inflows from tributary streams contributed less than 1.5 percent of the total inflows. Releases through Mountain Island Dam accounted for about 81 percent of outflows from the reservoir, while Riverbend Steam Station withdrawals, which were equal to discharge from the facility, constituted about 13 percent of the reservoir withdrawals. About 5.5 percent of the withdrawals from the reservoir were for water supply. Strong thermal stratification was seldom observed in Mountain Island Lake during April 1996-September 1997. As a result, dissolved-oxygen concentrations were only infrequently less than 4 milligrams per liter, and seldom less than 5 milligrams per liter throughout the entire reservoir, including the coves. The Riverbend Steam Station thermal discharge had a pronounced effect on surface-water temperatures near the outfall. McDowell Creek, which drains to McDowell Creek cove, receives treated wastewater from a large municipal facility and has exhibited signs of poor water-quality conditions in the past. During April 1996-September 1997, concentrations of nitrate, ammonia, total phosphorus, and chlorophyll a were higher in McDowell Creek cove

  2. Climate extremes are associated with invertebrate taxonomic and functional composition in mountain lakes.

    PubMed

    Boersma, Kate S; Nickerson, Avery; Francis, Clinton D; Siepielski, Adam M

    2016-11-01

    Climate change is expected to increase climate variability and the occurrence of extreme climatic events, with potentially devastating effects on aquatic ecosystems. However, little is known about the role of climate extremes in structuring aquatic communities or the interplay between climate and local abiotic and biotic factors. Here, we examine the relative influence of climate and local abiotic and biotic conditions on biodiversity and community structure in lake invertebrates. We sampled aquatic invertebrates and measured environmental variables in 19 lakes throughout California, USA, to test hypotheses of the relationship between climate, local biotic and environmental conditions, and the taxonomic and functional structure of aquatic invertebrate communities. We found that, while local biotic and abiotic factors such as habitat availability and conductivity were the most consistent predictors of alpha diversity, extreme climate conditions such as maximum summer temperature and dry-season precipitation were most often associated with multivariate taxonomic and functional composition. Specifically, sites with high maximum temperatures and low dry-season precipitation housed communities containing high abundances of large predatory taxa. Furthermore, both climate dissimilarity and abiotic dissimilarity determined taxonomic turnover among sites (beta diversity). These findings suggest that while local-scale environmental variables may predict alpha diversity, climatic variability is important to consider when projecting broad-scale aquatic community responses to the extreme temperature and precipitation events that are expected for much of the world during the next century.

  3. Diatom-inferred Holocene record of moisture variability in Lower Bear Lake, San Bernardino Mountains, California, USA

    NASA Astrophysics Data System (ADS)

    Starratt, S.; Kirby, M. E.

    2014-12-01

    Although Holocene diatom records from southern California lakes have been difficult to obtain, diatoms have been found in Lower Bear Lake (LBL) sediments, providing a 9200-year hydroclimatological record for the San Bernardino Mountains. Based on several physical and chemical properties as well as gastropod and ostracod assemblages. Kirby et al. (2012, QSR,46:57-65) inferred nine decadal to multi-centennial pluvial episodes (five major (PE-V to PE-I), four minor (PE-IIIa-c, PE-IIa) in sediment core BBLVC05-1 (34o15'20" N, 116o55'20" W; 4.5 m long). Here, we consider the implications of this new diatom data. The diatom record shows a gradual increase in salinity during the Holocene, corroborating the inference of decreasing lake size made by Kirby et al. (2012). The longest pluvial (PE-V; 9170?-8250 cal yr BP), is dominated by small fragilaroid taxa, indicating fresh, slightly alkaline waters. An increase in halophilic taxa at ~8700 cal yr BP suggests a several-decades-long drier interval within the pluvial. PE-IV (7000-6400 cal yr BP) is dominated by benthic taxa, including relatively high numbers of epiphytic taxa, indicating an increase in aquatic macrophytes. The abundance of Aulacoseira in PE-IV and PE-III (3350-3000 cal yr BP) suggests increased turbulence due to increased storminess. PE-III and PE-II (850-700 cal yr BP) contain greater abundances of benthic (epiphytic) and halophilic species, although the latter never dominate the assemblage. PE-I (500-476 cal yr BP) was not sampled. Aerophilic taxa comprise up to 3% of the assemblage during pluvial events suggesting increased erosion during those periods and the presence of symbiotic species throughout the record indicates nitrogen-depleted waters. The diatom data generally support the occurrence of multiple pluvials over the Holocene with the most sustained occurring in the early Holocene. Furthermore, the diatom data suggest LBL likely diminished in size through the Holocene becoming more saline in the

  4. Traditional Medicine in the Pristine Village of Prokoško Lake on Vranica Mountain, Bosnia and Herzegovina

    PubMed Central

    Šarić-Kundalić, Broza; Fritz, Elisabeth; Dobeš, Christoph; Saukel, Johannes

    2010-01-01

    The results of an ethnobotanical study conducted in the pristine village of Prokoško Lake (Vranica Mountain, Bosnia and Herzegovina) in summer 2007 is presented. Informal interviews involving 12 informants known as “traditional healers” provided data from 43 plants used in 82 prescriptions. The applied plants were used for a broad spectrum of indications. The most frequent were gastro-intestinal tract ailments, blood system disorders, skin ailments, respiratory tract ailments and urinary-genital tract ailments. The most frequent preparation was an infusion. Other often used preparations were ointments or balms and decocts. The special Bosnian balms known as “mehlems” were prepared from freshly chopped or freshly pressed herbal parts of various plant species. Warmed resins from Abies or Picea species, raw cow or pig lard, olive oil and honey served as basis. The traditional doctors, who usually worked as a team, enjoyed such a good reputation that people from all over the country were visiting in search of alternative ways to cure their ailments and diseases. The practical techniques applied by the healers and some of their attitudes and values are reported. PMID:21179347

  5. Airborne geophysical surveys over the eastern Adirondacks, New York State

    USGS Publications Warehouse

    Shah, Anjana K.

    2016-01-01

    Airborne geophysical surveys were conducted in the eastern Adirondacks from Dec. 7, 2015 - Dec. 21, 2015, by Goldak Airborne Surveys. The area was flown along a draped surface with a nominal survey height above ground of 200 meters. The flight line spacing was 250 meters for traverse lines and 2500 meters for control lines. Here we present downloadable magnetic and radiometric (gamma spectrometry) data from those surveys as image (Geotiff) and flight line data (csv format).BackgroundThe Eastern Adirondacks region was known for iron mining in the 1800's and 1900's but it also contains deposits of rare earth minerals. Rare earth minerals are used in advanced technology such as in cell phones, rechargeable batteries and super-magnets. In many areas rare earth minerals appear to be associated with iron ore.The surveys were flown in order to map geologic variations in three dimensions. Magnetic surveys measure subtle changes in Earth's magnetic field that reflect different types of buried rock, such as iron-rich ore bodies. Radiometric methods detect naturally occurring gamma particles. The energy spectra of these particles can be used to estimate relative amounts of potassium, uranium and thorium (also referred to as gamma ray spectrometry), which are sometimes associated with rare earth elements. Together, these data provide insights into the regional tectonic and magmatic history as well as mineral resources in the area.

  6. Diatom diversity in chronically versus episodically acidified adirondack streams

    USGS Publications Warehouse

    Passy, S.I.; Ciugulea, I.; Lawrence, G.B.

    2006-01-01

    The relationship between algal species richness and diversity, and pH is controversial. Furthermore, it is still unknown how episodic stream acidification following atmospheric deposition affects species richness and diversity. Here we analyzed water chemistry and diatom epiphyton dynamics and showed their contrasting behavior in chronically vs. episodically acidic streams in the Adirondack region. Species richness and diversity were significantly higher in the chronically acidic brown water stream, where organic acidity was significantly higher and the ratio of inorganic to organic monomeric aluminum significantly lower. Conversely, in the episodically acidic clear water stream, the inorganic acidity and pH were significantly higher and the diatom communities were very species-poor. This suggests that episodic acidification in the Adirondacks may be more stressful for stream biota than chronic acidity. Strong negative linear relationships between species diversity, Eunotia exigua, and dissolved organic carbon against pH were revealed after the influence of non-linear temporal trends was partialled out using a novel way of temporal modeling. ?? 2006 WILEY-VCH Verlag GmbH & Co. KGaA.

  7. Direct and indirect effects of vertical mixing, nutrients and ultraviolet radiation on the bacterioplankton metabolism in high-mountain lakes from southern Europe

    NASA Astrophysics Data System (ADS)

    Durán, C.; Medina-Sánchez, J. M.; Herrera, G.; Villar-Argaiz, M.; Villafañe, V. E.; Helbling, E. W.; Carrillo, P.

    2014-05-01

    As a consequence of global change, modifications in the interaction among abiotic stressors on aquatic ecosystems have been predicted. Among other factors, UVR transparency, nutrient inputs and shallower epilimnetic layers could alter the trophic links in the microbial food web. Currently, there are some evidences of higher sensitiveness of aquatic microbial organisms to UVR in opaque lakes. Our aim was to assess the interactive direct and indirect effects of UVR (through the excretion of organic carbon - EOC - by algae), mixing regime and nutrient input on bacterial metabolism. We performed in situ short-term experiments under the following treatments: full sunlight (UVR + PAR, >280 nm) vs. UVR exclusion (PAR only, >400 nm); ambient vs. nutrient addition (phosphorus (P; 30 μg PL-1) and nitrogen (N; up to final N : P molar ratio of 31)); and static vs. mixed regime. The experiments were conducted in three high-mountain lakes of Spain: Enol [LE], Las Yeguas [LY] and La Caldera [LC] which had contrasting UVR transparency characteristics (opaque (LE) vs. clear lakes (LY and LC)). Under ambient nutrient conditions and static regimes, UVR exerted a stimulatory effect on heterotrophic bacterial production (HBP) in the opaque lake but not in the clear ones. Under UVR, vertical mixing and nutrient addition HBP values were lower than under the static and ambient nutrient conditions, and the stimulatory effect that UVR exerted on HBP in the opaque lake disappeared. By contrast, vertical mixing and nutrient addition increased HBP values in the clear lakes, highlighting for a photoinhibitory effect of UVR on HBP. Mixed regime and nutrient addition resulted in negative effects of UVR on HBP more in the opaque than in the clear lakes. Moreover, in the opaque lake, bacterial respiration (BR) increased and EOC did not support the bacterial carbon demand (BCD). In contrast, bacterial metabolic costs did not increase in the clear lakes and the increased nutrient availability even

  8. Short-term responses of wetland vegetation after liming of an Adirondack watershed

    SciTech Connect

    Mackun, I.R.; Leopold, D.J.; Raynal, D.J. )

    1994-08-01

    Watershed liming has been suggested as a long-term mitigation strategy for lake acidity, particularly in areas subject to high levels of acidic deposition. However, virtually no information has been available on the impacts of liming on wetland vegetation. In 1989, 1100 Mg of limestone (83.5% CaCO[sub 3]) were aerially applied to 48% (100 ha) of the Woods Lake watershed in the west-central Adirondack region of New York as part of the first comprehensive watershed liming study in North America. We inventoried wetland vegetation in 1.0-m[sup 2] plots before liming and during the subsequent 2 yr. Within this period liming influenced the cover, frequency, or importance values of only 6 of 64 wetland taxa. The cover of Sphagnum spp. and of the cespitose sedge Carex interior decreased in control relative to limed plots, and cover of the rhizomatous sedge Cladium mariscoides increased nearly threefold in limed areas. These two sedges, which are relatively tall, are characteristic of more calcareous habitats. Cover of the grass Muhlenbergia uniflora, cover and importance were adversely affected or inhibited by lime. It is unclear whether liming directly inhibited the growth of these three small-statured species, or whether the adverse effects of lime were mediated through shifts in competitive interactions with other species. The limited responses that we observed to liming, along with changes that occurred in control plots over the study period, may indicate that in the short term watershed liming was no more of a perturbation than the environmental factors responsible for natural annual variation in wetland communities.

  9. Climate and environmental changes over the past 150 years inferred from the sediments of Chaiwopu Lake, central Tianshan Mountains, northwest China

    NASA Astrophysics Data System (ADS)

    Ma, Long; Wu, Jinglu; Abuduwaili, Jilili

    2013-04-01

    We used a 55-cm sediment core from shallow Chaiwopu Lake in the central Tianshan Mountains of Xinjiang, northwest China, to investigate climate and environmental changes in this arid region over the past ~150 years. The core was dated using 137Cs. We compared temporal changes in several sediment variables with recent meteorological and tree-ring records. Organic matter had a positive correlation with the Palmer Drought Severity Index in the central Tianshan Mountains, and the δ13C of organic matter had a positive correlation with regional temperature. We applied constrained incremental sum-of-squares cluster analysis to element concentrations in the core and identified three distinct zones: (1) 55-46 cm, ~1860-1910, (2) 46-26 cm, ~1910-1952, and (3) 26-0 cm, 1952-present. Between 1880 and 1910 AD, following the Little Ice Age (LIA), the sediment environment was relatively stable, climate was cold and dry, and the lake water displayed high salinity, in contrast to conditions during the LIA. During the LIA, westerlies carried more water vapor into Central Asia when the North Atlantic Oscillation was in a negative phase, and encountered the enhanced Siberia High, which probably led to increased precipitation. In the period 1910-1950 AD, the lake was shallow and the regional climate was unstable, with high temperatures and humidity. In the last ~15-20 years, human activities caused an increase in sediment magnetic susceptibility, and heavy metal and total phosphorus concentrations in the sediment were substantially enriched. Mean annual temperature displays a warming trend over the past 50 years, and the lowest temperature was observed in the 1950s. There has been an increase in annual total precipitation since the 1990s. The combined influences of climate and human activity on the lake environment during this period were faithfully recorded in sediments of Chaiwopu Lake. This study provides a scientific basis for environmental management and protection.

  10. Exploring the Stable Isotope Record of Lake Carpenter: A Lacustrine Sequence in the Aptian-Albian Cretaceous Cedar Mountain Formation, Utah, USA

    NASA Astrophysics Data System (ADS)

    Montgomery, E.; Al-Suwaidi, A. H.; Suarez, M. B.; Kirkland, J. I.; Suarez, C. A.

    2014-12-01

    The Cedar Mountain Formation (CMF) represents the earliest deposition of terrestrial Cretaceous strata in the USA, recording significant changes in biota and climate. Understanding these transitions requires improved time constraints and high-resolution proxy records. Here we present new δ13C (organic carbon & carbonate) chemostratigraphic record of a lacustrine sequence in a locality named "Lake Carpenter", near Moab, Utah. Lake Carpenter (LC) comprises interbedded limestone and mudstone units of the Ruby Ranch Member of the CMF. Results of the chemostratigraphy are constrained by detrital zircons from the section allowing correlation of the chemostratigraphy to the carbon isotope segments C9 to C11 (Bralower et al., 1999) spanning the Late Aptian to Early Albian, and supported by previous litho- and chemostratigraphic work in the CMF. δ13Corg values show a pronounced negative stepped excursion, of -6‰ with values reaching -32.3 ‰ occurring in conjunction with an increase in TOC. This negative excursion is followed by a positive recovery, with values of ~-25‰ and relatively low TOC. δ13Ccarb records positive values, up to +8‰, in the lowermost part of the section (< ~7m) followed by a decrease to ~-7 ‰. δ18Ocarb over this interval records values between -2 and -4‰ followed by a decrease to ~-7‰. The lowermost portion of the LC section is indicative of relatively deep lacustrine environment in which organic carbon burial influenced the δ13C of dissolved inorganic carbon (DIC) in the lake. This lower δ13C of DIC may be due to increased upwelling and/or turnover and recycling of organic carbon in the lake. Variability of δ13Ccarb and δ18Ocarb values may reflect changes in water supply to the lake, or climatic variability resulting in the lake drying out. δ13Corg values may be affected by local lake dynamics, including variations in organic carbon storage and changes in algal productivity, perhaps also indicative of changes in nutrient

  11. Differences Between the “Chinese AMS Score” and the Lake Louise Score in the Diagnosis of Acute Mountain Sickness

    PubMed Central

    Wu, Jialin; Gu, Haoran; Luo, Yongjun

    2016-01-01

    Abstract The Chinese AMS score (CAS) is used in clinical medicine and research to diagnosis acute mountain sickness (AMS). However, the Lake Louise Score (LLS) is the well-accepted standard for diagnosing AMS. The difference between the CAS and LLS questionnaires is that the CAS considers more nonspecific symptoms. The aim of the present study was to evaluate differences in AMS prevalence according to the LLS and CAS criteria. We surveyed 58 males who traveled from Chongqing (300 m) to Lhasa (3658 m) via the Qinghai-Tibet train. Cases of AMS were diagnosed using LLS and CAS questionnaires in a few railway stations at different evaluation areas along the road. We subsequently evaluated discrepancies in values related to the prevalence of AMS determined using the 2 types of questionnaires (CAS and LLS). The prevalence of CAS-diagnosed AMS indicated that the percentage of AMS cases among the 58 young men was 29.3% in Golmud, 60.3% in Tanggula, 63.8% in Lhasa, 22.4% on the first day after arrival in Lhasa, 27.6% on the second day, 24.1% on the third day, and 12.1% on the fourth day. The prevalence of LLS-diagnosed AMS in Golmud was 10.3%, 38% in Lhasa, and 6.9% on day 1, the prevalence in each station was lower than that as assessed by the CAS. Our experimental data indicate that AMS diagnoses ascertained using the CAS indicate a higher AMS prevalence than those ascertained using the LLS. Through statistical analysis, the CAS seems capable of effectively diagnosing AMS as validated by LLS (sensitivity 61.8%, specificity 92.7%). PMID:27227918

  12. Differences Between the "Chinese AMS Score" and the Lake Louise Score in the Diagnosis of Acute Mountain Sickness.

    PubMed

    Wu, Jialin; Gu, Haoran; Luo, Yongjun

    2016-05-01

    The Chinese AMS score (CAS) is used in clinical medicine and research to diagnosis acute mountain sickness (AMS). However, the Lake Louise Score (LLS) is the well-accepted standard for diagnosing AMS. The difference between the CAS and LLS questionnaires is that the CAS considers more nonspecific symptoms. The aim of the present study was to evaluate differences in AMS prevalence according to the LLS and CAS criteria. We surveyed 58 males who traveled from Chongqing (300 m) to Lhasa (3658 m) via the Qinghai-Tibet train. Cases of AMS were diagnosed using LLS and CAS questionnaires in a few railway stations at different evaluation areas along the road. We subsequently evaluated discrepancies in values related to the prevalence of AMS determined using the 2 types of questionnaires (CAS and LLS). The prevalence of CAS-diagnosed AMS indicated that the percentage of AMS cases among the 58 young men was 29.3% in Golmud, 60.3% in Tanggula, 63.8% in Lhasa, 22.4% on the first day after arrival in Lhasa, 27.6% on the second day, 24.1% on the third day, and 12.1% on the fourth day. The prevalence of LLS-diagnosed AMS in Golmud was 10.3%, 38% in Lhasa, and 6.9% on day 1, the prevalence in each station was lower than that as assessed by the CAS. Our experimental data indicate that AMS diagnoses ascertained using the CAS indicate a higher AMS prevalence than those ascertained using the LLS. Through statistical analysis, the CAS seems capable of effectively diagnosing AMS as validated by LLS (sensitivity 61.8%, specificity 92.7%).

  13. Non-primary layering in some Adirondack orthogneisses

    SciTech Connect

    Levy, R.; McLelland, J.; Ritter, A. . Geology Dept.)

    1993-03-01

    Metamorphic, as opposed to primary, layering has been shown to be important in many tectonites. Within orthogneisses additional types of non-primary layering are common and have important genetic implications. Here the authors cite three Adirondack examples. (1) Hyde School Gneiss of the Adirondack Lowlands contains semi-continuous layers of foliated amphibolite arranged parallel to contacts and early foliation and disrupted by pegmatitic, alaskitic, and tonalitic host rock. Layering appears to be the result of penetration of amphibolite by granitoid magma first along extensional fractures and then parallel to foliation. Intrusion is envisaged to take place in active shear zones initially occupied by foliated amphibolite that is subsequently penetrated parallel to foliation by granitoids. (2) South of Elizabethtown foliated, isoclinally folded gabbroic anorthosite is well layered with garnetiferous amphibolite, quartz-feldspar gneiss, and calcsilicate. Because of rock composition, the layering cannot be due to metavolcanic sequences nor can disruption be attributed to partial melting. A satisfactory interpretation is that gabbroic anorthosite intruded mafic and carbonate-rich rocks in lit-par-lit fashion. (3) North of Speculator a garnetiferous amphibolite/gabbro has been intruded by granite now containing xenoliths, some with ophitic opx. Much of the layering in the granite consists of clots of plagioclase, garnet, pyroxene (chloritized) arranged in parallel. These are interpreted as small xenoliths of garnetiferous amphibolite/gabbro entrained into the granitic magma and strung out in the direction of flow. These examples provide further evidence that layering can develop during magmatic emplacement and need not represent primary stratification. Assignment of a primary origin to such layering necessarily results in misinterpretation of geologic history.

  14. Organochlorine compounds and current-use pesticides in snow and lake sediment in Rocky Mountain National Park, Colorado, and Glacier National Park, Montana, 2002-03

    USGS Publications Warehouse

    Mast, M. Alisa; Foreman, William T.; Skaates, Serena V.

    2006-01-01

    Organochlorine compounds and current-use pesticides were measured in snow and lake-sediment samples from Rocky Mountain National Park in Colorado and Glacier National Park in Montana to determine their occurrence and distribution in high-elevation aquatic ecosystems. The U.S. Geological Survey, in cooperation with the National Park Service, collected snow samples at eight sites in Rocky Mountain National Park and at eight sites in Glacier National Park during spring of 2002 and 2003 just prior to the start of snowmelt. Surface sediments were collected from 11 lakes in Rocky Mountain National Park and 10 lakes in Glacier National Park during summer months of 2002 and 2003. Samples were analyzed for organochlorine compounds by gas chromatography with electron-capture detection and current-use pesticides by gas chromatography with electron-impact mass spectrometry. A subset of samples was reanalyzed using a third instrumental technique (gas chromatography with electron-capture negative ion mass spectrometry) to verify detected concentrations in the initial analysis and to investigate the presence of additional compounds. For the snow samples, the pesticides most frequently detected were endosulfan, dacthal, and chlorothalonil, all of which are chlorinated pesticides that currently are registered for use in North America. Concentrations of these pesticides in snow were very low, ranging from 0.07 to 2.36 nanograms per liter. Of the historical-use pesticides, hexachlorobenzene, dieldrin, and trans-nonachlor were detected in snow but only in one sample each. Annual deposition rates of dacthal, endosulfan, and chlorothalonil were estimated at 0.7 to 3.0 micrograms per square meter. These estimates are likely biased low because they do not account for pesticide deposition during summer months. For the lake-sediment samples, DDE (p,p'-dichlorodiphenyldichoroethene) and DDD (p,p'-dichlorodiphenyldichoroethane) were the most frequently detected organochlorine compounds. DDE

  15. Compound-specific stable isotopes of organic compounds from lake sediments track recent environmental changes in an alpine ecosystem, Rocky Mountain National Park, Colorado

    USGS Publications Warehouse

    Enders, S.K.; Pagani, M.; Pantoja, S.; Baron, J.S.; Wolfe, A.P.; Pedentchouk, N.; Nunez, L.

    2008-01-01

    Compound-specific nitrogen, carbon, and hydrogen isotope records from sediments of Sky Pond, an alpine lake in Rocky Mountain National Park (Colorado, United States of America), were used to evaluate factors contributing to changes in diatom assemblages and bulk organic nitrogen isotope records identified in lake sediments across Colorado, Wyoming, and southern Montana. Nitrogen isotopic records of purified algal chlorins indicate a substantial shift in nitrogen cycling in the region over the past ???60 yr. Temporal changes in the growth characteristics of algae, captured in carbon isotope records in and around Sky Pond, as well as a -60??? excursion in the hydrogen isotope composition of algal-derived palmitic acid, are coincident with changes in nitrogen cycling. The confluence of these trends is attributed to an increase in biologically available nitrogenous compounds caused by an expansion of anthropogenic influences and temporal changes in catchment hydrology and nutrient delivery associated with meltwater dynamics. ?? 2008, by the American Society of Limnology and Oceanography, Inc.

  16. Historical streamflows of Double Mountain Fork of Brazos River and water-surface elevations of Lake Alan Henry, Garza County, Texas, water years 1962-2010

    USGS Publications Warehouse

    Asquith, William H.; Vrabel, Joseph

    2011-01-01

    The U.S. Geological Survey (USGS), in cooperation with the City of Lubbock, Texas, operates two surface-water stations in Garza County, Tex.: USGS streamflow-gaging station 08079600 Double Mountain Fork Brazos River at Justiceburg, Tex., and 08079700 Lake Alan Henry Reservoir, a water-supply reservoir about 60 miles southeast of Lubbock, Tex., and about 10 miles east of Justiceburg, Tex. The streamflow and water-surface elevation data from the two stations are useful to water-resource managers and planners in support of forecasting and water-resource infrastructure operations and are used in regional hydrologic studies.

  17. Numerical modeling of the Snowmass Creek paleoglacier, Colorado, and climate in the Rocky Mountains during the Bull Lake glaciation (MIS 6)

    SciTech Connect

    Eric M. Leonard; Mitchell A. Plummer; Paul E. Carrara

    2014-04-01

    Well-preserved moraines from the penultimate, or Bull Lake, glaciation of Snowmass Creek Valley in the Elk Range of Colorado present an opportunity to examine the character of the high-altitude climate in the Rocky Mountains during Marine Oxygen Isotope Stage 6. This study employs a 2-D coupled mass/energy balance and flow model to assess the magnitudes of temperature and precipitation change that could have sustained the glacier in mass-balance equilibrium at its maximum extent during the Bull Lake glaciation. Variable substrate effects on glacier flow and ice thickness make the modeling somewhat more complex than in geologically simpler settings. Model results indicate that a temperature depression of about 6.7°C compared with the present (1971–2000 AD) would have been necessary to sustain the Snowmass Creek glacier in mass-balance equilibrium during the Bull Lake glaciation, assuming no change in precipitation amount or seasonality. A 50% increase or decrease from modern precipitation would have been coupled with 5.2°C and 9.1°C Bull Lake temperature depressions respectively. Uncertainty in these modeled temperature depressions is about 1°C.

  18. Numerical modeling of the Snowmass Creek paleoglacier, Colorado, and climate in the Rocky Mountains during the Bull Lake glaciation (MIS 6)

    NASA Astrophysics Data System (ADS)

    Leonard, Eric M.; Plummer, Mitchell A.; Carrara, Paul E.

    2014-11-01

    Well-preserved moraines from the penultimate, or Bull Lake, glaciation of Snowmass Creek Valley in the Elk Range of Colorado (USA) present an opportunity to examine the character of the high-altitude climate in the Rocky Mountains during Marine Oxygen Isotope Stage 6. This study employs a 2-D coupled mass/energy balance and flow model to assess the magnitudes of temperature and precipitation change that could have sustained the glacier in mass-balance equilibrium at its maximum extent during the Bull Lake glaciation. Variable substrate effects on glacier flow and ice thickness make the modeling somewhat more complex than in geologically simpler settings. Model results indicate that a temperature depression of about 6.7°C compared with the present (1971-2000 AD) would have been necessary to sustain the Snowmass Creek glacier in mass-balance equilibrium during the Bull Lake glaciation, assuming no change in precipitation amount or seasonality. A 50% increase or decrease from modern precipitation would have been coupled with 5.2°C and 9.1°C Bull Lake temperature depressions respectively. Uncertainty in these modeled temperature depressions is about 1°C.

  19. New lakes in de-glaciating high-mountain regions - a challenge for integrative research about hazard protection and sustainable use

    NASA Astrophysics Data System (ADS)

    Haeberli, W.

    2012-12-01

    As a consequence of rapid glacier vanishing, an increasing number of smaller and larger lakes are forming in high-mountain regions worldwide. Such new lakes can be touristic landscape attractions and may also represent interesting potentials for hydropower production. However, they more and more often come into existence at the foot of very large and steep icy mountain walls, which are progressively destabilizing due to changing surface and subsurface ice conditions. The probability of far-reaching flood and debris flow catastrophes caused by impact waves from large rock/ice avalanches into lakes may still appear to be small now but steadily increases for long time periods to come. Corresponding projects related to hazard protection and sustainable use should be combined in an integrative and participatory planning process. This planning process must start soon, because the development in nature is fast and most likely accelerating. Technical tools for creating the necessary scientific knowledge basis at local to regional scales exist and can be used. The location of future new lakes in topographic bed depressions of now still glacier-covered areas can be quite safely assessed on the basis of morphological criteria or by applying ice thickness estimates using digital terrain information. Models for ice-thickness estimates couple the depth to bedrock via the basal shear stress with the surface slope and provide a (relative) bed topography which is much more robust than the (absolute) value of the calculated ice thickness. Numerical models at various levels of sophistication can be used to simulate possible future glacier changes in order to establish the probable time of lake formation and the effects of glacier shrinking on runoff seasonality and water supply. The largest uncertainties thereby relate to the large uncertainties of (absolute) ice thickness and mass/energy fluxes at the surface (climate scenarios, precipitation and albedo changes, etc.). Combined

  20. Interactive effects of vertical mixing, nutrients and ultraviolet radiation: in situ photosynthetic responses of phytoplankton from high mountain lakes in Southern Europe

    NASA Astrophysics Data System (ADS)

    Helbling, E. W.; Carrillo, P.; Medina-Sánchez, J. M.; Durán, C.; Herrera, G.; Villar-Argaiz, M.; Villafañe, V. E.

    2013-02-01

    Global change, together with human activities, has resulted in increasing amounts of organic material (including nutrients) that water bodies receive. This input further attenuates the penetration of solar radiation, leading to the view that opaque lakes are more "protected" from solar ultraviolet radiation (UVR) than clear ones. Vertical mixing, however, complicates this view as cells are exposed to fluctuating radiation regimes, for which the effects have, in general, been neglected. Furthermore, the combined impacts of mixing, together with those of UVR and nutrient inputs are virtually unknown. In this study, we carried out complex in situ experiments in three high mountain lakes of Spain (Lake Enol in the National Park Picos de Europa, Asturias, and lakes Las Yeguas and La Caldera in the National Park Sierra Nevada, Granada), used as model ecosystems to evaluate the joint impact of these climate change variables. The main goal of this study was to address the question of how short-term pulses of nutrient inputs, together with vertical mixing and increased UVR fluxes modify the photosynthetic responses of phytoplankton. The experimentation consisted in all possible combinations of the following treatments: (a) solar radiation: UVR + PAR (280-700 nm) versus PAR (photosynthetically active radiation) alone (400-700 nm); (b) nutrient addition (phosphorus (P) and nitrogen (N)): ambient versus addition (P to reach to a final concentration of 30 μg P L-1, and N to reach N:P molar ratio of 31); and (c) mixing: mixed (one rotation from surface to 3 m depth (speed of 1 m 4 min-1, total of 10 cycles)) versus static. Our findings suggest that under ambient nutrient conditions there is a synergistic effect between vertical mixing and UVR, increasing phytoplankton photosynthetic inhibition and excretion of organic carbon (EOC) from opaque lakes as compared to algae that received constant mean irradiance within the epilimnion. The opposite occurs in clear lakes where

  1. Interactive effects of vertical mixing, nutrients and ultraviolet radiation: in situ photosynthetic responses of phytoplankton from high mountain lakes of Southern Europe

    NASA Astrophysics Data System (ADS)

    Helbling, E. W.; Carrillo, P.; Medina-Sanchez, J. M.; Durán, C.; Herrera, G.; Villar-Argaiz, M.; Villafañe, V. E.

    2012-07-01

    Global change, together with human activities had resulted in increasing amounts of organic material (including nutrients) received by water bodies. This input further attenuates the penetration of solar radiation leading to the view that opaque lakes are more "protected" from solar ultraviolet radiation (UVR) than clear ones. Vertical mixing, however, complicates this view as cells are exposed to fluctuating radiation regimes, which effects have in general been neglected. Even more, the combined impacts of mixing, together with those of UVR and nutrients input are virtually unknown. In this study, we carried out in situ experiments in three high mountain lakes of Spain (Lake Enol in Asturias, and lakes Las Yeguas and La Caldera in Granada) to determine the combined effects of these three variables associated to global change on photosynthetic responses of natural phytoplankton communities. The experimentation consisted in all possible combinations of the following treatments: (a) solar radiation: UVR + PAR (280-700 nm) versus PAR alone (400-700 nm); (b) nutrient addition (phosphorus (P) and nitrogen (N)): ambient versus addition (P to reach to a final concentration of 30 μg P l-1, and N to reach a N : P molar ratio of 31) and, (c) mixing: mixed (one rotation from surface to 3 m depth (speed of 1 m every 4 min, total of 10 cycles) versus static. Our findings suggest that under in situ nutrient conditions there is a synergistic effect between vertical mixing and UVR, increasing phytoplankton photosynthetic inhibition and EOC from opaque lakes as compared to algae that received constant mean irradiance within the epilimnion. The opposite occurs in clear lakes where antagonistic effects were determined, with mixing partially counteracting the negative effects of UVR. Nutrients input mimicking atmospheric pulses from Saharan dust, reversed this effect and clear lakes became more inhibited during mixing, while opaque lakes benefited from the fluctuating irradiance

  2. National Dam Inspection Program. Blue Mountain Lake Dam (NDI ID PA 00627, PA DER 45-34), Delaware River Basin, Unnamed Tributary of Brodhead Creek, Pennsylvania. Phase I Inspection Report

    DTIC Science & Technology

    1981-08-01

    mounood [ ,3Q,,s’t,lt l oo &I on .. .. .+ MCCR DELAWARE RIVER BASIN Avallability Co4e _Avail- and/tim’eor - 11As pecial8J BLUE MOUNTAIN LAKE DAM...concrete reservoir outlet pipe discharges into the spillway channel about 50 feet downstream of the embankment. The inlet gate, which is located in the...impoundment at the upstream end of the pipe , is no longer operable. b. Lncation. Blue Mountain Lake Dam is located on a branch of Ruliffs Run, about 2.5

  3. An empirical approach to modeling methylmercury concentrations in an Adirondack stream watershed

    USGS Publications Warehouse

    Burns, Douglas A.; Nystrom, Elizabeth A.; Wolock, David M.; Bradley, Paul M.; Riva-Murray, Karen

    2014-01-01

    Inverse empirical models can inform and improve more complex process-based models by quantifying the principal factors that control water quality variation. Here we developed a multiple regression model that explains 81% of the variation in filtered methylmercury (FMeHg) concentrations in Fishing Brook, a fourth-order stream in the Adirondack Mountains, New York, a known “hot spot” of Hg bioaccumulation. This model builds on previous observations that wetland-dominated riparian areas are the principal source of MeHg to this stream and were based on 43 samples collected during a 33 month period in 2007–2009. Explanatory variables include those that represent the effects of water temperature, streamflow, and modeled riparian water table depth on seasonal and annual patterns of FMeHg concentrations. An additional variable represents the effects of an upstream pond on decreasing FMeHg concentrations. Model results suggest that temperature-driven effects on net Hg methylation rates are the principal control on annual FMeHg concentration patterns. Additionally, streamflow dilutes FMeHg concentrations during the cold dormant season. The model further indicates that depth and persistence of the riparian water table as simulated by TOPMODEL are dominant controls on FMeHg concentration patterns during the warm growing season, especially evident when concentrations during the dry summer of 2007 were less than half of those in the wetter summers of 2008 and 2009. This modeling approach may help identify the principal factors that control variation in surface water FMeHg concentrations in other settings, which can guide the appropriate application of process-based models.

  4. Hydrogeologic controls of surface-water chemistry in the Adirondack region of New York State

    USGS Publications Warehouse

    Peters, N.E.; Driscoll, C.T.

    1987-01-01

    Relationships between surface-water discharge, water chemistry, and watershed geology were investigated to evaluate factors affecting the sensitivity of drainage waters in the Adirondack region of New York to acidification by atmospheric deposition. Instantaneous discharge per unit area was derived from relationships between flow and staff-gage readings at 10 drainage basins throughout the region. The average chemical composition of the waters was assessed from monthly samples collected from July 1982 through July 1984. The ratio of flow at the 50-percent exceedence level to the flow at the 95-percent exceedence level of flow duration was negatively correlated with mean values of alkalinity or acid-neutralizing capacity (ANC), sum of basic cations (SBC), and dissolved silica, for basins containing predominantly aluminosilicate minerals and little or no carbonate-bearing minerals. Low ratios are indicative of systems in which flow is predominately derived from surface- and ground-water storage, whereas high ratios are characteristic of watersheds with variable flow that is largely derived from surface runoff. In an evaluation of two representative surface-water sites, concentrations of ANC, SBC, and dissolved silica, derived primarily from soil mineral weathering reactions. decreased with increasing flow. Furthermore, the ANC was highest at low flow when the percentage of streamflow derived from ground water was maximum. As flow increased, the ANC decreased because the contribution of dilute surface runoff and lateral flow through the shallow acidic soil horizons to total flow increased. Basins having relatively high ground-water contributions to total flow, in general, have large deposits of thick till or stratified drift. A major factor controlling the sensitivity of these streams and lakes to acidification is the relative contribution of ground water to total discharge. ?? 1987 Martinus Nijhoff/Dr W. Junk Publishers.

  5. Quantitative reconstructions of mid- to late holocene climate and vegetation in the north-eastern altai mountains recorded in lake teletskoye

    NASA Astrophysics Data System (ADS)

    Rudaya, Natalia; Nazarova, Larisa; Novenko, Elena; Andreev, Andrei; Kalugin, Ivan; Daryin, Andrei; Babich, Valery; Li, Hong-Chun; Shilov, Pavel

    2016-06-01

    We report the first high-resolution (20-50 years) mid- to late Holocene pollen records from Lake Teletskoye, the largest lake in the Altai Mountains, in south-eastern West Siberia. Generally, the mid- to late Holocene (the last 4250 years) vegetation of the north-eastern Altai, as recorded in two studied sediment cores, is characterised by Siberian pine-spruce-fir forests that are similar to those of the present day. A relatively cool and dry interval with July temperatures lower than those of today occurred between 3.9 and 3.6 ka BP. The widespread distribution of open, steppe-like communities with Artemisia, Chenopodiaceae and Cyperaceae reflects maximum deforestation during this interval. After ca. 3.5 ka BP, the coniferous mountain taiga spread significantly, with maximum woody coverage and taiga biome scores between ca. 2.7 and 1.6 ka BP. This coincides well with the highest July temperature (approximately 1 °C higher than today) intervals. A short period of cooling about 1.3-1.4 ka BP could have been triggered by the increased volcanic activity recorded across the Northern Hemisphere. A new period of cooling started around 1100-1150 CE, with the minimum July temperatures occurring between 1450 and 1800 CE.

  6. The missing piece: sediment records in remote Mountain lakes confirm glaciers being secondary sources of persistent organic pollutants.

    PubMed

    Schmid, Peter; Bogdal, Christian; Blüthgen, Nancy; Anselmetti, Flavio S; Zwyssig, Alois; Hungerbühler, Konrad

    2011-01-01

    After atmospheric deposition and storage in the ice, glaciers are temporary reservoirs of persistent organic pollutants (POPs). Recently, the hypothesis that melting glaciers represent secondary sources of these pollutants has been introduced by investigations of the historical trend of POPs in a dated sediment core from the proglacial Alpine Lake Oberaar. Here, the hypothesis is further confirmed by the comparison of sediment data gathered from two Alpine lakes with a glaciated and a nonglaciated hydrological catchment. The two lakes (Lake Engstlen and Lake Stein in the Bernese Alps in Switzerland) are situated only 8 km apart at similar altitude and in the same meteorological catchment. In the nonglacial lake sediment of Lake Engstlen, PCBs and DDT (polychlorinated biphenyls and dichlorodiphenyl trichloroethane) levels culminated with the historic usage of these chemicals some 30-50 years ago. In the glacial Lake Stein, this peak was followed by a reincrease in the 1990s, which goes along with the accelerated melting of the adjacent glacier. This study confirms the hypothesis of glaciers being a secondary source of these pollutants and is in accordance with the earlier findings in Lake Oberaar.

  7. Reconnaissance geologic map and mineral resource potential of the Gearhart Mountain Wilderness and Roadless Area (6225), Lake and Klamath counties, Oregon

    USGS Publications Warehouse

    Walker, George W.; Ridenour, James

    1982-01-01

    The Gearhart Mountain Wilderness, Lake and Klamath Counties, Oreg., is devoid of mines and mineral prospects and there are no known mining claims within the area. Furthermore, the results of this mineral appraisal indicate that there is little likelihood that commercial deposits of metallic minerals will be found in the area. Commercial uranium deposits, like those at the White King and Lucky Lass mines about 16 mi (~25 km) to the southeast of the wilderness, and deposits of mercury, like those south-southeast of the wilderness, are not likely to be found within the wilderness, even though all of these areas are characterized by middle and late Cenozoic intrusive and extrusive volcanic rocks. Rock of low commercial value for construction purposes is present, but better and more accessible deposits are present in adjacent regions. There is no evidence to indicate that mineral fuels are present in the area. Higher than normal heat floe characterizes the region containing Gerheart Mountain, indicating that it may have some, as yet undefined, potential for the development of geothermal energy. Data are not available to determine whether this higher than normal heat flow is meaningful in terms of a potential energy source or as a guide to possible future exploration; lack of thermal springs or other evidence of localized geothermal anomalies within the Gerhart Mountain suggest, however, that the potential for the development of geothermal energy is probably low.

  8. Pollen-based reconstruction of vegetational and climatic change over the past ~30 ka at Shudu Lake in the Hengduan Mountains of Yunnan, southwestern China

    PubMed Central

    Wortley, Alexandra H.; Wang, Yu-Fei; Blackmore, Stephen; Li, Cheng-Sen

    2017-01-01

    The Hengduan Mountains, with a distinct altitudinal differentiation and strong vertical vegetation zonation, occupy an important position in southwestern China as a global hotspot of biodiversity. Pollen analysis of lake sediments sampled along an altitudinal gradient in this region helps us to understand how this vegetation zonation arose and how it has responded to climate change and human impacts through time. Here we present a ~30-ka pollen record and interpret it in terms of vegetational and climatic change from a 310 cm-long core from Shudu Lake, located in the Hengduan Mountains region. Our results suggest that from 30 to 22 cal. ka BP, the vegetation was dominated by steppe/grassland (comprising mainly Artemisia, Poaceae and Polygonaceae) and broad-leaved forest (primarily Quercus, Betula and Castanopsis) in the lake catchment, reflecting a relatively warm, wet climate early in this phase and slightly warmer, drier conditions late in the phase. The period between 22 and 13.9 cal. ka BP was marked by a large expansion of needle- and broad-leaved mixed forest (Pinus, Abies and Quercus) and a decline in the extent of steppe/grassland, indicating warming, drying climatic conditions followed by a cold, wet period. Between 13.9 and 3 cal. ka BP, steppe/grassland expanded and the area covered by needle- and broad-leaved mixed forest reduced, implying a fluctuating climate dominated by warm and humid conditions. After 3 cal. ka BP, the vegetation was characterized by an increase in needle-leaved forest and reduction in steppe/grassland, suggesting warming and drying climate. A synthesis of palynological investigations from this and other sites suggests that the vegetation succession patterns seen along an altitudinal gradient in northwestern Yunnan since the Late Pleistocene are comparable, but that each site has its own characteristics probably due to the influences of altitude, topography, microclimate and human impact. PMID:28182711

  9. Pollen-based reconstruction of vegetational and climatic change over the past ~30 ka at Shudu Lake in the Hengduan Mountains of Yunnan, southwestern China.

    PubMed

    Yao, Yi-Feng; Song, Xiao-Yan; Wortley, Alexandra H; Wang, Yu-Fei; Blackmore, Stephen; Li, Cheng-Sen

    2017-01-01

    The Hengduan Mountains, with a distinct altitudinal differentiation and strong vertical vegetation zonation, occupy an important position in southwestern China as a global hotspot of biodiversity. Pollen analysis of lake sediments sampled along an altitudinal gradient in this region helps us to understand how this vegetation zonation arose and how it has responded to climate change and human impacts through time. Here we present a ~30-ka pollen record and interpret it in terms of vegetational and climatic change from a 310 cm-long core from Shudu Lake, located in the Hengduan Mountains region. Our results suggest that from 30 to 22 cal. ka BP, the vegetation was dominated by steppe/grassland (comprising mainly Artemisia, Poaceae and Polygonaceae) and broad-leaved forest (primarily Quercus, Betula and Castanopsis) in the lake catchment, reflecting a relatively warm, wet climate early in this phase and slightly warmer, drier conditions late in the phase. The period between 22 and 13.9 cal. ka BP was marked by a large expansion of needle- and broad-leaved mixed forest (Pinus, Abies and Quercus) and a decline in the extent of steppe/grassland, indicating warming, drying climatic conditions followed by a cold, wet period. Between 13.9 and 3 cal. ka BP, steppe/grassland expanded and the area covered by needle- and broad-leaved mixed forest reduced, implying a fluctuating climate dominated by warm and humid conditions. After 3 cal. ka BP, the vegetation was characterized by an increase in needle-leaved forest and reduction in steppe/grassland, suggesting warming and drying climate. A synthesis of palynological investigations from this and other sites suggests that the vegetation succession patterns seen along an altitudinal gradient in northwestern Yunnan since the Late Pleistocene are comparable, but that each site has its own characteristics probably due to the influences of altitude, topography, microclimate and human impact.

  10. Diversity of extremophilic bacteria in the sediment of high-altitude lakes located in the mountain desert of Ojos del Salado volcano, Dry-Andes.

    PubMed

    Aszalós, Júlia Margit; Krett, Gergely; Anda, Dóra; Márialigeti, Károly; Nagy, Balázs; Borsodi, Andrea K

    2016-09-01

    Ojos del Salado, the highest volcano on Earth is surrounded by a special mountain desert with extreme aridity, great daily temperature range, intense solar radiation, and permafrost from 5000 meters above sea level. Several saline lakes and permafrost derived high-altitude lakes can be found in this area, often surrounded by fumaroles and hot springs. The aim of this study was to gain information about the bacterial communities inhabiting the sediment of high-altitude lakes of the Ojos del Salado region located between 3770 and 6500 m. Altogether 11 sediment samples from 4 different altitudes were examined with 16S rRNA gene based denaturing gradient gel electrophoresis and clone libraries. Members of 17 phyla or candidate divisions were detected with the dominance of Proteobacteria, Acidobacteria, Actinobacteria and Bacteroidetes. The bacterial community composition was determined mainly by the altitude of the sampling sites; nevertheless, the extreme aridity and the active volcanism had a strong influence on it. Most of the sequences showed the highest relation to bacterial species or uncultured clones from similar extreme environments.

  11. Bacterial diversity and composition during rain events with and without Saharan dust influence reaching a high mountain lake in the Alps.

    PubMed

    Peter, Hannes; Hörtnagl, Paul; Reche, Isabel; Sommaruga, Ruben

    2014-12-01

    The diversity of airborne microorganisms that potentially reach aquatic ecosystems during rain events is poorly explored. Here, we used a culture-independent approach to characterize bacterial assemblages during rain events with and without Saharan dust influence arriving to a high mountain lake in the Austrian Alps. Bacterial assemblage composition differed significantly between samples with and without Saharan dust influence. Although alpha diversity indices were within the same range in both sample categories, rain events with Atlantic or continental origins were dominated by Betaproteobacteria, whereas those with Saharan dust intrusions were dominated by Gammaproteobacteria. The high diversity and evenness observed in all samples suggests that different sources of bacteria contributed to the airborne assemblage collected at the lake shore. During experiments with bacterial assemblages collected during rain events with Saharan dust influence, cell numbers rapidly increased in sterile lake water from initially ∼3 × 103 cell ml-1 to 3.6-11.1 x105 cells ml-1 within 4-5 days, and initially, rare taxa dominated at the end of the experiment. Our study documents the dispersal of viable bacteria associated to Saharan dust intrusions travelling northwards as far as 47° latitude.

  12. Lake biota response to human impact and local climate during the last 200 years: A multi-proxy study of a subalpine lake (Tatra Mountains, W Carpathians).

    PubMed

    Hamerlík, Ladislav; Dobríková, Daniela; Szarlowicz, Katarzyna; Reczynski, Witold; Kubica, Barbara; Šporka, Ferdinand; Bitušík, Peter

    2016-03-01

    Element content, loss-on-ignition, chironomid analysis and (210)Pb dating were applied on a sediment core from a subalpine Tatra lake (Popradské pleso) to reveal the response of aquatic biota to eutrophication induced by human activities in the lake catchment. The lead dating indicates that the 0-8 cm section of the core represents the past ca 200 years, ending at ~1814 AD. Comparing the key changes of the proxies with human activities that are historically well documented, four phases of the recent lake development were distinguished: (1) a pre-tourism phase, (2) a phase of increasing touristic activity and early cottage development, (3) a phase of eutrophication, and (4) a phase of post-eutrophication. Neither touristic activity, nor early cottage development around the lake (1st and 2nd phases) had considerable influence on the chironomid assemblage structure or organic content of the lake. The most significant change both in chironomid assemblage structure and loss-on-ignition occurred during the 3rd phase, when a big tourist hotel was built close by the lake and started contaminating it via direct wastewater input. However, the structure of the chironomid assemblage has not changed significantly over time and the dominating taxa remained the same during the whole period. Parallel with the nutrient signal of the paleo assemblage, a secondary signal has been identified as the ratio of rheophilic taxa on total abundance that did not correlate with the sediment's organic content, and is most likely driven by local climatic oscillations. Changes of most of metal elements concentrations reflected rather bigger scale changes of industrial activities than local scale human disturbances. Our results indicate that hydromorphological properties can moderate the impact of organic pollution on the lake biota.

  13. A computational approach to Quaternary lake-level reconstruction applied in the central Rocky Mountains, Wyoming, USA

    NASA Astrophysics Data System (ADS)

    Pribyl, Paul; Shuman, Bryan N.

    2014-07-01

    Sediment-based reconstructions of late-Quaternary lake levels provide direct evidence of hydrologic responses to climate change, but many studies only provide approximate lake-elevation curves. Here, we demonstrate a new method for producing quantitative time series of lake elevation based on the facies and elevations of multiple cores collected from a lake's margin. The approach determines the facies represented in each core using diagnostic data, such as sand content, and then compares the results across cores to determine the elevation of the littoral zone over time. By applying the approach computationally, decisions are made systematically and iteratively using different facies classification schemes to evaluate the associated uncertainty. After evaluating our assumptions using ground-penetrating radar (GPR), we quantify past lake-elevation changes, precipitation minus evapotranspiration (ΔP-ET), and uncertainty in both at Lake of the Woods and Little Windy Hill Pond, Wyoming. The well-correlated (r = 0.802 ± 0.002) reconstructions indicate that water levels at both lakes fell at > 11,300, 8000-5500, and 4700-1600 cal yr BP when ΔP - ET decreased to - 50 to - 250 mm/yr. Differences between the reconstructions are typically small (10 ± 24 mm/yr since 7000 cal yr BP), and the similarity indicates that our reconstruction method can produce statistically comparable paleohydrologic datasets across networks of sites.

  14. Lake Store Finnsjøen - a key for understanding Lateglacial/early Holocene vegetation and ice sheet dynamics in the central Scandes Mountains

    NASA Astrophysics Data System (ADS)

    Paus, Aage; Boessenkool, Sanne; Brochmann, Christian; Epp, Laura Saskia; Fabel, Derek; Haflidason, Haflidi; Linge, Henriette

    2015-08-01

    The Lateglacial (LG) deglaciation and vegetation development in the Scandes Mountains has been debated for a century. Here we present new evidence from microfossils, radiocarbon dated plant macrofossils and sedimentary ancient DNA from laminated sediments in Lake Store Finnsjøen (1260 m a.s.l.) at Dovre, Central Norway. Combined with previous results from three other Dovre lakes, this allows for new interpretations of events during and immediately after the LG deglaciation. The Finnsjøen sediments present the first uninterrupted record of local vegetation development in the Scandes Mountains from the late Younger Dryas (YD), ca 12,000 cal years BP, to the early Holocene around 9700 cal years BP. The local vegetation in late YD/early Holocene was extremely sparse with pioneer herbs (e.g. Artemisia norvegica, Beckwithia, Campanula cf. uniflora, Koenigia, Oxyria, Papaver, Saxifraga spp.) and dwarf-shrubs (Betula nana, Salix including Salix polaris). From 11,300 cal years BP, local vegetation rapidly closed with dominant Dryas, Saxifraga spp., and Silene acaulis. From ca 10,700 cal years BP, open birch-forests with juniper, Empetrum nigrum and other dwarf-shrubs developed. Pine forests established within the area from 10,300 cal years BP. We identified the cold Preboreal Oscillation (PBO), not earlier described from pollen data in South Norway, around 11,400 cal years BP by a regional pollen signal. Distinct local vegetation changes were not detected until the post-PBO warming around 11,300 cal years BP. Apparently, the earlier warming at the YD/Holocene transition at 11,650 cal years BP was too weak and short-lived for vegetation closure at high altitudes at Dovre. For the first time, we demonstrate a regional glacier readvance and local ice cap formations during the YD in the Scandes Mountains. In two of the deep lakes with small catchments, YD glaciation blocked sedimentation without removing old sediments and caused a hiatus separating sediments of the ice

  15. Late Quaternary landscape evolution in the Kunlun Mountains and Qaidam Basin, Northern Tibet: A framework for examining the links between glaciation, lake level changes and alluvial fan formation

    USGS Publications Warehouse

    Owen, L.A.; Finkel, R.C.; Haizhou, M.; Barnard, P.L.

    2006-01-01

    The Qaidam Basin in Northern Tibet is one of the largest hyper-arid intermontane basins on Earth. Alluvial fans, pediment surfaces, shorelines and a thick succession of sediments within the basin, coupled with moraines and associated landforms in the adjacent high mountain catchments of the Kunlun Mountains, record a complex history of Late Quaternary paleoenvironmental change and landscape evolution. The region provides an ideal natural laboratory to examine the interaction between tectonics and climate within a continent-continent collision zone, and to quantify rates of landscape evolution as controlled by climate and the associated glacial and hydrological changes in hyper-arid and adjacent high-altitude environments. Geomorphic mapping, analysis of landforms and sediments, and terrestrial cosmogenic radionuclide surface exposure and optically stimulated luminescence dating serve to define the timing of formation of Late Quaternary landforms along the southern and northwestern margins of the Qaidam Basin, and in the Burhan Budai Shan of the Kunlun Mountains adjacent to the basin on the south. These dates provide a framework that suggests links between climatic amelioration, deglaciation, lake desiccation and alluvial fan evolution. At least three glacial advances are defined in the Burham Budai Shan of the Kunlun Mountains. On the northern side of this range these occurred in the penultimate glacial cycle or early in the last glacial cycle, during the Last Glacial Maximum (LGM)/Lateglacial and during the Holocene. On the south side of the range, advances occurred during the penultimate glacial cycle, MIS-3, and possibly the LGM, Lateglacial or Holocene. Several distinct phases of alluvial fan sedimentation are likewise defined. Alluvial fans formed on the southern side of the Kunlun Mountains prior to 200 ka. Ice-contact alluvial fans formed during the penultimate glacial and during MIS-3. Extensive incised alluvial fans that form the main valley fills north of

  16. Past soil erosion history recorded by lake sediments in mountain areas (north and south French Alps): complex interactions with climatic and human activities

    NASA Astrophysics Data System (ADS)

    Giguet-Covex, C.; Poulenard, J.; Arnaud, F.; Disnar, J.-R.; Sabatier, P.; Wilhelm, B.; Jouffroy-Bapicot, I.; Rey, P.-J.; David, F.; Malet, E.

    2012-04-01

    Erosion rates and patterns are influenced both by hydrological activity and the evolution of soil-vegetation cover. This soil-vegetation cover is in turn impacted by climatic changes and human activities through deforestation, grazing and agriculture. Such land uses are reported in mountain areas since several millennia (the Neolithic or Bronze Age in the Alps). The effects of these activities and climatic changes on erosion and above all on soil cover are relatively few documented. However, a good knowledge of these processes is important to better evaluate the future evolution of soils and the sustainability for agricultural practices, in the context of global change. Because lakes act as traps of erosion products, lake sediments represent interesting continuous archives of past soil evolution and erosion. They provide a unique opportunity to reconstruct at high resolution the soil history over long time periods and thus to determine the timing of changes in response to climate and/or anthropogenic pressures. As a result of the Pygmalion research program, we present the study of two small mountain catchment in north (Lake Anterne, 2063 m asl) and south French Alps (Lake Lauzanier, 2285 m asl), covering the Holocene and the last 1000 years, respectively. To trace the past soil erosion erosion history and bring arguments about the origin of changes, mineral and organic geochemical analyses were performed and combined with quantitative reconstructions of terrigenous inputs. To emphasize our assumptions about the origins of recorded changes, a pluridisciplinary approach (palynology, archaeology...) was also adopted. The study of Lake Anterne shows the second half of the Holocene is characterized by four important phases of erosion. These phases are underlined by high flood frequencies and different geochemical composition of sediments. These geochemical signatures reveal changes of sediment sources related to different erosion patterns. In particular, the first phase

  17. Trace-metal concentrations, waters from selected sky lakes, streams and springs, northern Shawangunk Mountains, New York: geologic and ecologic implications

    USGS Publications Warehouse

    Friedman, J.D.; Huth, P.C.; Smiley, D.

    1990-01-01

    Reconnaissance sampling and chemical analysis of water from selected lakes, streams and springs of the northern Shawangunk Mountains in 1987 to 1988 to determine the influence of lithology on trace-metal concentrations in surface water, and to establish a base level of concentration of 27 selected metals by ICP-AES and Hg by cold-vapor AAS methods, for geochemical exploration, ecologic, acid-rain, and climatic-change studies, have yielded trace-metal concentrations greater than detection limits for 10 metallic elements. Eighteen additional metallic elements were also present in trace quantities below the quantitative detection limit. Two distinct geochemical populations are related to source lithology and pH. -from Authors

  18. Mafic rocks of the Adirondack Highlands: One suite or many

    SciTech Connect

    Whitney, P.R. . New York State Museum)

    1993-03-01

    Mafic rocks in the granulite facies terrane of the Adirondack Highlands form at least 3 and possibly as many as 6 groups, based on field, petrographic, and geochemical criteria. Most abundant is the olivine metagabbro-amphibolite group (OMA), equivalent to the mafic suite'' of Olson (J. Petrol. 33:471, 1992). OMA occurs in irregular to tabular bodies, locally with intrusive relations, in all major rock types in the E and central Highlands. OMA is strongly olivine normative and forms a continuous differentiation series (Olson, 1992). Plagioclase-two pyroxene-garnet granulites (PGG) form dikes up to several m wide, in anorthositic host rocks. PGG are ferrogabbroic or ferrodioritic and approximately silica saturated. Two subgroups differ sharply in Mg, P, and trace elements. Ferrodiorite and monzodiorite gneisses (FMG), quartz normative and commonly migmatitic, occur in several large bodies in the NE Highlands and as extensive thin sheets in the W and SE Highlands, in association with anorthositic rocks. Three subgroups are distinguishable using Mg/Fe ratios and trace elements. Major element least-squares modeling suggests that both PGG and FMG could be derived by fractionation of gabbroic anorthosite liquids. A differentiation series is not evident, however, and both trace element (Ba, Rb, Sr, Zr and REE) data and normative plagioclase (An [>=] plag. in anorthosite) indicate a more complex origin. One subgroup of FMG may be early cumulates of the mangerite-charnockite suite. The chemistry of OMA, PGG, and FMG reflects their evolved nature and cannot be readily interpreted in terms of magma sources.

  19. The application of an integrated biogeochemical model (PnET-BGC) to five forested watersheds in the Adirondack and Catskill regions of New York

    USGS Publications Warehouse

    Chen, L.; Driscoll, C.T.; Gbondo-Tugbawa, S.; Mitchell, M.J.; Murdoch, Peter S.

    2004-01-01

    PnET-BGC is an integrated biogeochemical model formulated to simulate the response of soil and surface waters in northern forest ecosystems to changes in atmospheric deposition and land disturbances. In this study, the model was applied to five intensive study sites in the Adirondack and Catskill regions of New York. Four were in the Adirondacks: Constable Pond, an acid-sensitive watershed; Arbutus Pond, a relatively insensitive watershed; West Pond, an acid-sensitive watershed with extensive wetland coverage; and Willy's Pond, an acid-sensitive watershed with a mature forest. The fifth was Catskills: Biscuit Brook, an acid-sensitive watershed. Results indicated model-simulated surface water chemistry generally agreed with the measured data at all five sites. Model-simulated internal fluxes of major elements at the Arbutus watershed compared well with previously published measured values. In addition, based on the simulated fluxes, element and acid neutralizing capacity (ANC) budgets were developed for each site. Sulphur budgets at each site indicated little retention of inputs of sulphur. The sites also showed considerable variability in retention of NO3-. Land-disturbance history and in-lake processes were found to be important in regulating the output of NO3- via surface waters. Deposition inputs of base cations were generally similar at these sites. Various rates of base cation outputs reflected differences in rates of base cation supply at these sites. Atmospheric deposition was found to be the largest source of acidity, and cation exchange, mineral weathering and in-lake processes served as sources of ANC. ?? 2004 John Wiley and Sons, Ltd.

  20. The evaluation of 3cm-wavelength radar for mapping surface deposits in the Bristol Lake/Granite Mountain area, Mojave Desert, California

    NASA Technical Reports Server (NTRS)

    Sugiura, R.; Sabins, F. F., Jr.

    1980-01-01

    Surface deposits in the Bristol Lake/Granite Mountains area, Mojave Desert, California were mapped using high resolution 3 cm wavelength radar images. The surface deposits range from silt to boulders in size and were separated into six radar-rock units on the basis of radar return signatures (brightness and texture) and geomorphic expression. Field reconnaissance of the six units showed that the brightness of the radar signatures on the images correlates with the surface roughness of each unit. Two major radar signatures anomalies were noted during the study. A dark radar signature for the large sand ridges in the Kelso Dunes area and a distinct northwest trending contrast boundary between bright and dark radar signatures in the Bristol Dry Lake area. Field reconnaissance of the two areas indicated that near surface moisture may be the cause of dark signatures. Dune areas with little to no vegetation produce a dark signature, whereas areas with sparse to moderate vegetation produce an intermediate to dark signature.

  1. Mechanisms and Magnitude of Cenozoic Crustal Extension in the Vicinity of Lake Mead, Nevada and the Beaver Dam Mountains, Utah: Geochemical, Geochronological,Thermochronological and Geophysical Constraints

    NASA Astrophysics Data System (ADS)

    Almeida, Rafael V.

    The central Basin and Range Province of Nevada and Utah was one of the first areas in which the existence of widespread low-angle normal faults or detachments was first recognized. The magnitude of associated crustal extension is estimated by some to be large, in places increasing original line lengths by as much as a factor of four. However, rock mechanics experiments and seismological data cast doubt on whether these structures slipped at low inclination in the manner generally assumed. In this dissertation, I review the evidence for the presence of detachment faults in the Lake Mead and Beaver Dam Mountains areas and place constraints on the amount of extension that has occurred there since the Miocene. Chapter 1 deals with the source-provenance relationship between Miocene breccias cropping out close to Las Vegas, Nevada and their interpreted source at Gold Butte, currently located 65 km to the east. Geochemical, geochronological and thermochronological data provide support for that long-accepted correlation, though with unexpected mismatches requiring modification of the original hypothesis. In Chapter 2, the same data are used to propose a refinement of the timing of ~1.45 Ga anorogenic magmatism, and the distribution of Proterozoic crustal boundaries. Chapter 3 uses geophysical methods to address the subsurface geometry of faults along the west flank of the Beaver Dam Mountains of southwestern Utah. The data suggest that the range is bounded by steeply inclined normal faults rather than a regional-scale detachment fault. Footwall folding formerly ascribed to Miocene deformation is reinterpreted as an expression of Cretaceous crustal shortening. Fission track data presented in Chapter 4 are consistent with mid-Miocene exhumation adjacent to high-angle normal faults. They also reveal a protracted history dating back to the Pennsylvanian-Permian time, with implications for the interpretation of other basement-cored uplifts in the region. A key finding of this

  2. Mature and old-growth riparian forests: structure, dynamics, and effects on Adirondack stream habitats.

    PubMed

    Keeton, William S; Kraft, Clifford E; Warren, Dana R

    2007-04-01

    Riparian forests regulate linkages between terrestrial and aquatic ecosystems, yet relationships among riparian forest development, stand structure, and stream habitats are poorly understood in many temperate deciduous forest systems. Our research has (1) described structural attributes associated with old-growth riparian forests and (2) assessed linkages between these characteristics and in-stream habitat structure. The 19 study sites were located along predominantly first- and second-order streams in northern hardwood-conifer forests in the Adirondack Mountains of New York (U.S.A.). Sites were classified as mature forest (6 sites), mature with remnant old-growth trees (3 sites), and old-growth (10 sites). Forest-structure attributes were measured over stream channels and at varying distances from each bank. In-stream habitat features such as large woody debris (LWD), pools, and boulders were measured in each stream reach. Forest structure was examined in relation to stand age using multivariate techniques, ANOVA, and linear regression. We investigated linkages between forest structure and stream characteristics using similar methods, preceded by information-theoretic modeling (AIC). Old-growth riparian forest structure is more complex than that found in mature forests and exhibits significantly greater accumulations of aboveground tree biomass, both living and dead. In-stream LWD volumes were significantly (alpha = 0.05) greater at old-growth sites (200 m3/ha) compared to mature sites (34 m3/ha) and were strongly related to the basal area of adjacent forests. In-stream large-log densities correlated strongly with debris-dam densities. AIC models that included large-log density, debris-dam density, boulder density, and bankfull width had the most support for predicting pool density. There were higher proportions of LWD-formed pools relative to boulder-formed pools at old-growth sites as compared to mature sites. Old-growth riparian forests provide in

  3. Dating of pollen samples from the sediment core of Lake St Anne in the East Carpathian Mountains, Romania

    NASA Astrophysics Data System (ADS)

    Hubay, Katalin; Katalin Magyari, Enikö; Braun, Mihály; Schabitz, Frank; Molnár, Mihály

    2016-04-01

    Lake St Anne (950 m a.s.l.) is situated in the Ciomadul volcano crater, the youngest volcano in the Carpathians. Aims driving forward the studies there are twofold, one is dating the latest eruption of the Ciomadul volcano and the other is the multi-proxy palaeoenvironmental reconstruction of this region. The sediment of Lake St Anne was sampled several times already, but never reached the bottom of the lake before. During the winter of 2013 at a new core location drilling started at 600 cm water depth and finally reached the bottom of the lake sediment at approximately 2300 cm including water depth. As for all multi-proxy studies essential requirement was to build a reliable chronology. Sediments were dated by radiocarbon method. Previous radiocarbon dates were measured on plant macrofossils, charcoal, Cladocera eggs, chironomid head capsules and bulk lake sediments. Lake St Anne has volcanic origin and there is intensive upwelling of CO2it is important to study and take into consideration, whether there is any local reservoir effect at the case of samples where it could be problematic. Furthermore the late part of the sediment section (between 15,000 and 30,000 cal. yr BP) has low organic matter content (less than 2-4%) with scarcity of datable plant macrofossil material. In this review a different fraction of pollen samples with terrestrial origin was tested and studied as a novel sample type for the radiocarbon dating. Pollen samples were extracted from the lake sediment cores. This type of organic material could be an ideal candidate for radiocarbon based chronological studies as it has terrestrial source and is present in the whole core in contrast with the terrestrial macrofossils. Although the pollen remains were present in the whole core, in many cases their amount give a challenge even for the AMS technic. Samples were measured with EnvironMICADAS AMS and its gas ion source in the HEKAL laboratory (Debrecen, Hungary). We examine the reliability the

  4. Functional groups and activities of bacteria in a highly acidic volcanic mountain stream and lake in Patagonia, Argentina.

    PubMed

    Wendt-Potthoff, Katrin; Koschorreck, M

    2002-01-01

    Acidic volcanic waters are naturally occurring extreme habitats that are subject of worldwide geochemical research but have been little investigated with respect to their biology. To fill this gap, the microbial ecology of a volcanic acidic river (pH approximately equal to 0-1.6), Rio Agrio, and the recipient lake Caviahue in Patagonia, Argentina, was studied. Water and sediment samples were investigated for Fe(II), Fe(III), methane, bacterial abundances, biomass, and activities (oxygen consumption, iron oxidation and reduction). The extremely acidic river showed a strong gradient of microbial life with increasing values downstream and few signs of life near the source. Only sulfide-oxidizing and fermentative bacteria could be cultured from the upper part of Rio Agrio. However, in the lower part of the system, microbial biomass and oxygen penetration and consumption in the sediment were comparable to non-extreme aquatic habitats. To characterize similarities and differences of chemically similar natural and man-made acidic waters, our findings were compared to those from acidic mining lakes in Germany. In the lower part of the river and the lake, numbers of iron and sulfur bacteria and total biomass in sediments were comparable to those known from acidic mining lakes. Bacterial abundance in water samples was also very similar for both types of acidic water (around 10(5) mL(-1)). In contrast, Fe(II) oxidation and Fe(III) reduction potentials appeared to be lower despite higher biogenic oxygen consumption and higher photosynthetic activity at the sediment-water interface. Surprisingly, methanogenesis was detected in the presence of high sulfate concentrations in the profundal sediment of Lake Caviahue. In addition to supplementing microbiological knowledge on acidic volcanic waters, our study provides a new view of these extreme sites in the general context of aquatic habitats.

  5. Detail climate reconstructions based on combined geochemistry of lake sediments and tree-ring data by the example of Altai Mountains

    NASA Astrophysics Data System (ADS)

    Kalugin, Ivan; Darin, Andrey; Myglan, Vladimir; Ovchinnikov, Dmitry; Holodova, Lyudmila

    2010-05-01

    Our knowledge of climate change with associated forcing during the last thousand-years remains limited because that cannot be studied thoroughly by instrumental data. So it is an actual task to find high resolution paleoclimate records and to compare it with recent patterns of short-period oscillations. Combination of lake sediments and tree rings appears to be effective for understanding of regional climate variability. The Altai mountain range in Central Asia has a climate divide between Siberian forests in the North and arid areas of Central Asia in the South. This region is characterized by the highest degree of continentality. In winter, due to the prevailing stable Siberian High, cold and dry arctic air masses are predominant. In summer, humid air masses from the Atlantic Ocean as well as recycled moisture are the main sources of precipitation. There are several dendrochronologies (up to 1700 years long) and annual reconstructions by Teletskoye Lake sediments (3000 years) in Altai region. They are calibrated by data from 14 local weather stations (time series up to 80 years) and Barnaul station (170 years) as well. The frequencies analysis of tree-ring width chronologies from Altai using by the spectral analysis shows that high frequencies are dominate. Most of cycles have periodicity up to 40 years. Maximum amplitude were found for 32.3, 142,9 and 200 year. High frequencies (2-40 years) are explain more 60% variability of tree-ring width chronologies. Decadal variabilities are found for 32.3, 40.0 and 43.5 years. Last two cycles are the same as Brikner cycle and could explain decadal moisture variability in Altai and Central Asia. Typical mountains lakes - Teletskoye and Kucherla - with accumulation rate of the fine-grained sediments 0,5-2 mm/year and free of human impact are selected to take sediment cores. A new generation of X-Ray Fluorescence instruments - the XRF scanner on Synchrotron Radiation - allows providing extraordinary high-resolution (up to 0

  6. Biological cycling of nitrogen in a Rocky Mountain alpine lake, with emphasis on the physiological and ecological effects of acidification

    SciTech Connect

    Angelo, R.T.

    1989-01-01

    This study examined nitrogen cycling interactions occurring among the heterotrophic and autotrophic plankton of a softwater, oligotrophic alpine lake. Its major objectives were (1) to compare the influences of internal (regenerative) and external nitrogen supply processes on watercolumn primary production, (2) to identify the food web components contributing most to regenerative and assimilative fluxes of nitrogen, and (3) to evaluate the sensitivity of the limnetic nitrogen cycle to lake acidification. Field and laboratory experiments were based on isotopic tracer ({sup 15}N, {sup 14}C, {sup 3}H) methodologies plankton size-fractionation and metabolic inhibitor techniques, and short-term bioassay procedures; supporting data were gathered on lake physicochemical and biological properties. Measured aqueous nutrient concentrations, the results of {sup 14}CO{sub 2}-based snowmelt and nutrient enrichment bioassays, and physiological indicators of algal nutrient status collectively demonstrated that phytoplankton nitrogen demand greatly exceeded nitrogen supply. Both NH{sub 4}{sup +} and NO{sub 3}{sup {minus}} were quantitatively important forms of assimilatable nitrogen under ambient conditions. Mass balance considerations indicated that within-lake biogeochemical processes constituted a net sink for NO{sub 3}{sup {minus}}, whereas NH{sub 4}{sup +} production and consumption rates were approximately in balance on an ecosystem scale. Water-column regenerative and assimilative fluxes of NH{sub 4}{sup +} were strongly correlated. Meta- and protozooplankton were the principal sources of regenerated NH{sub 4}{sup +}; heterotrophic bacterioplankton were net consumers of NH{sub 4} {sup +}. Experimental reductions in metazooplankton populations markedly enhanced rates of NH{sub 4}{sup +} regeneration.

  7. From pumice to obsidian: eruptive behaviors that produce tephra-flow dyads. I- The AD1100 Big Glass Mountain eruption at Medicine Lake Volcano (California).

    NASA Astrophysics Data System (ADS)

    Giachetti, T.; Shea, T.; Gonnermann, H. M.; Donnelly-Nolan, J. M.; Ramsey, D. W.

    2014-12-01

    Associations of tephra and lava flow/domes produced by eruptions involving evolved magmas are a common occurrence in various types of volcanic settings (e.g. Pu'u Wa'awa'a ~114ka, Hawaii; South Mono ~AD625, California; Newberry Big Obsidian flow ~AD700, Oregon; Big Glass Mountain ~AD1100, California; Inyo ~AD1350, California, Chaitén AD2008-2009, Chile; Cordón Caulle AD2011-2012, Chile), ejecting up to a few cubic km of material (tephra+flow/dome). Most, if not all, of these eruptions have in common the paradoxical coexistence of (1) eruptive styles which are inferred to be sustained in nature (subplinian and plinian), with (2) a pulsatory behavior displayed by the resulting fall deposits, and (3) the coeval ejection of vesicular tephra and pyroclastic obsidian. Through two case studies, we explore this apparent set of paradoxes, and their significance in understanding transitions from explosive to effusive behavior. In this first case study (also cf. Leonhardi et al., same session), we present a new detailed stratigraphy of the AD1100 Big Glass Mountain eruption (Medicine Lake Volcano), along with a series of density measurements of tephra collected from several key units identified in the proximal fall deposits. The geochemical character of pumice and obsidian clasts from both the tephra and the obsidian flow is used to trace the origins of the different lithologies involved. We find that tens of waxing and waning cycles occurred during this eruption with at least two protracted phases, and that perhaps the term (sub)plinian may not be completely adequate to describe this particular eruption style. We also review models for the formation of juvenile pyroclastic obsidian in the context of rhyolitic eruptions.

  8. 1. OVERALL VIEW OF MILK LAKE, LOOKING NORTHEAST High ...

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

    1. OVERALL VIEW OF MILK LAKE, LOOKING NORTHEAST - High Mountain Dams in Upalco Unit, Milk Lake Dam, Ashley National Forest, 9.4 miles Northwest of Swift Creek Campground, Mountain Home, Duchesne County, UT

  9. 1. OVERALL VIEW OF KIDNEY LAKE, LOOKING SOUTHWEST High ...

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

    1. OVERALL VIEW OF KIDNEY LAKE, LOOKING SOUTHWEST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

  10. 2. VIEW SHOWING NATURAL SAND BEACH ON KIDNEY LAKE, LOOKING ...

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

    2. VIEW SHOWING NATURAL SAND BEACH ON KIDNEY LAKE, LOOKING WEST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

  11. 1. OVERALL VIEW OF BROWN DUCK LAKE, LOOKING SOUTHWEST ...

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

    1. OVERALL VIEW OF BROWN DUCK LAKE, LOOKING SOUTHWEST - High Mountain Dams in Upalco Unit, Brown Duck Lake Dam, Ashley National Forest, 4.4 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

  12. 2. OVERALL VIEW OF BROWN DUCK LAKE, LOOKING WEST ...

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

    2. OVERALL VIEW OF BROWN DUCK LAKE, LOOKING WEST - High Mountain Dams in Upalco Unit, Brown Duck Lake Dam, Ashley National Forest, 4.4 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

  13. Effect of whole catchment liming on the episodic acidification of two adirondack streams

    USGS Publications Warehouse

    Newton, R.M.; Burns, Douglas A.; Blette, V.L.; Driscoll, C.T.

    1996-01-01

    During the fall of 1989 7.7Mg/ha of calcium carbonate was applied on two tributary catchments (40 ha and 60 ha) to Woods Lake, a small (25 ha) acidic headwater lake in the western Adirondack region of New York. Stream-water chemistry in both catchment tributaries responded immediately. Acid-neutralizing capacity (ANC) increased by more than 200 ??eq/L in one of the streams and more than 1000 ??eq/L in the other, from pre-liming values which ranged from -25 to +40 ??eq/L. The increase in ANC was primarily due to increases in dissolved Ca2+ concentrations. Most of the initial response of the streams was due to the dissolution of calcite that fell directly into the stream channels and adjacent wetlands. A small beaver impoundment and associated wetlands were probably responsible for the greater response observed in one of the streams. After the liming of subcatchmentIV (60 ha), Ca2+ concentrations increased with increasing stream discharge in the stream during fall rain events, suggesting a contribution from calcite dissolved within the soil and transported to the stream by surface runoff or shallow interflow. Concentrations of other ions not associated with the calcite (e.g. Na+) decreased during fall rain events, presumably due to mixing of solute-rich base flow with more dilute shallow interflow. The strong relation between changes in Ca2+ and changes in NO3- concentrations during spring snowmelt, (r2 = 0.93, slope = 0.96, on an equivalent basis) suggests that both solutes had a common source in the organic horizon of the soil. Increases in NO3- concentrations during snowmelt were balanced by increases in Ca2+ that was released either directly from the calcite or from exchange sites, mitigating episodic acidification of the stream. However, high ambient NO3- concentrations and relatively low ambient Ca2+ concentrations in the stream during the spring caused the stream to become acidic despite the CaCO3 treatment. In stream WO2 (40ha), Ca2+ concentrations were much

  14. A 22 570 yr record of vegetational and climatic change from Wenhai Lake in the Hengduan Mountains biodiversity hotspot, Yunnan, Southwest China

    NASA Astrophysics Data System (ADS)

    Yao, Y. F.; Song, X. Y.; Wortley, A. H.; Blackmore, S.; Li, C. S.

    2014-09-01

    The Hengduan Mountains, with their strong altitudinal vegetation zonation, form a biodiversity hotspot which offers the potential for comparison between sites in order to understand how this zonation arose and how it has responded to climate change and human impacts through time. This paper is one of the studies covering a range of altitudes within this hotspot, and presents a 22 570 yr pollen record of vegetational and climatic change based on a core 320 cm in depth collected from Wenhai Lake on the Jade Dragon Snow Mountain, one of the highest peaks in the Hengduan Mountains region of Yunnan, Southwest China. From 22 570 to 21 140 cal. yr BP, the vegetation was dominated by broad-leaved forest (comprising mainly Quercus, Betula and Castanopsis), accompanied by coniferous Pinus and Abies and the drought-tolerant herb Artemisia, indicating a cool and dry climate. In the period between 21 140 and 19 350 cal. yr BP, the vegetation was still dominated by broad-leaved forest but with a notable increase in pollen of aquatic plants, implying a relatively warm and moderately humid climate. The period 19 350 to 17 930 cal. yr BP was a transition stage from broad-leaved forest to needle-leaved forest, reflecting a warm-humid climate at the beginning and a cold-dry one at the end. Between 17 930 and 9250 cal. yr BP, needle-leaved forest and broad-leaved forest alternated in dominance in the early stages, with the former taking the predominant position by the end of the period, suggesting a climate fluctuating between warm-humid and cold-dry. From 9250 cal. yr BP to present, the vegetation has been dominated by needle-leaved forest (comprising mainly Pinus and Abies), coupled with broad-leaved forest (mainly Quercus and Betula), reflecting a transition in climatic conditions from warm-humid to cold-humid. During this period, human activity increased in this region, with impacts on the vegetation which may be evidenced by the distinct decrease in Pinus and Quercus pollen and

  15. Timing of atmospheric precipitation in the Zagros Mountains inferred from a multi-proxy record from Lake Mirabad, Iran

    NASA Astrophysics Data System (ADS)

    Stevens, Lora R.; Ito, Emi; Schwalb, Antje; Wright, Herbert E.

    2006-11-01

    A sediment core 7.2 m long from Lake Mirabad, Iran, was examined for loss-on-ignition, mineralogy, oxygen-isotopic composition of authigenic calcite, and trace-element composition of ostracodes to complement earlier pollen and ostracode-assemblage studies. Pollen, ostracode-inferred lake level, and high Sr/Ca ratios indicate that the early Holocene (10000 to 6500 cal yr BP) was drier than the late Holocene. Low δ18O values during this interval are interpreted as resulting from winter-dominated precipitation, characteristic of a Mediterranean climate. Increasing δ18O values after 6500 cal yr BP signal a gradual increase in spring rains, which are present today. A severe 600-yr drought occurred at ca. 5500 cal yr BP, shortly after the transition from pistachio-almond to oak forest. During the late Holocene, two milder droughts occurred at about 1500 and 500 cal yr BP. Within the resolution of the record, no drought is evident during the collapse of the Akkadian empire (4200-3900 cal yr BP). Rather, a decrease in δ18O values to early-Holocene levels may indicate the return to a Mediterranean precipitation regime.

  16. Crustal Structure Beneath the Lake Ontario Region from Inverse Models of Potential Field and Seismic Data

    NASA Astrophysics Data System (ADS)

    Navarrete, L. C.; Benoit, M. H.; Ebinger, C. J.; Horowitz, F.

    2014-12-01

    The regions surrounding Lake Ontario (e.g. the Adirondack mountain region and its northern border with Canada) are among the most seismically active regions in the Eastern US. However, only scant knowledge exists of the location and geometry of faults, suture zones, or crustal thickness variations that may localize strain in the crust beneath sections of New York, Pennsylvania and Ontario. Our aim is to determine the crustal density and magnetic susceptibility contrasts (e.g., steep faults, intrusive bodies, Moho topography) which give rise to anomaly patterns and to place constraints on their geometries and locations. With a better understanding of these structures, we will examine how the distribution of the faults and steep contacts throughout the region compare with zones of active seismicity. Utilizing the North American Gravity Database, we created a profile that crosses a narrow Bouguer anomaly with steep gradients surrounded by Bouguer anomaly highs transecting the lake and extending onshore east of Rochester, subparallel to the seismically active Clarendon-Linden fault. Euler deconvolution and 'worm' analyses show that this narrow anomaly is bounded by east-dipping faults that extend to mid-crustal levels. We perform receiver function analyses of Earthscope TA stations in the region in order to constrain crustal thickness and lateral variations in Vp/Vs. These receiver functions at onshore sites in the area show complex Moho structure which partially explains our anomaly.Additionally, a vintage seismic profile coupled with the Lake Ontario bathymetry dataset was used to place constraints on sedimentary strata thicknesses and to identify structures within Proterozoic basement. Predictive models of crustal variations were created from a potential field profile, receiver functions, and a seismic profile to test interpretations. The Moho topography alone does not fully explain the short wavelength gravity anomaly, and a sedimentary basin of 3-5 km in depth is

  17. Three-year decline of magmatic CO2 emissions from soils of a Mammoth Mountain tree kill: Horseshoe Lake, CA, 1995-1997

    USGS Publications Warehouse

    Gerlach, T.M.; Doukas, M.P.; McGee, K.A.; Kessler, R.

    1998-01-01

    We used the closed chamber method to measure soil CO2 efflux over a three-year period at the Horseshoe Lake tree kill (HLTK) - the largest tree kill on Mammoth Mountain in central eastern California. Efflux contour maps show a significant decline in the areas and rates of CO2 emission from 1995 to 1997. The emission rate fell from 350 t d-1 (metric tons per day) in 1995 to 130 t d-1 in 1997. The trend suggests a return to background soil CO2 efflux levels by early to mid 1999 and may reflect exhaustion of CO2 in a deep reservoir of accumulated gas and/or mechanical closure or sealing of fault conduits transmitting gas to the surface. However, emissions rose to 220 t d-1 on 23 September 1997 at the onset of a degassing event that lasted until 5 December 1997. Recent reservoir recharge and/or extension-enhanced gas flow may have caused the degassing event.

  18. Rocky Mountain Arsenal NPDES Permit

    EPA Pesticide Factsheets

    Under NPDES permit CO-0035009, the U.S. Department of Interior's Fish and Wildlife Service is authorized to discharge from the Rocky Mountain Arsenal recycled water pipeline to Lower Derby Lake in Adams County, Colo.

  19. Fluid heterogeneity during granulite facies metamorphism in the Adirondacks: stable isotope evidence

    USGS Publications Warehouse

    Valley, J.W.; O'Neil, J.R.

    1984-01-01

    The preservation of premetamorphic, whole-rock oxygen isotope ratios in Adirondack metasediments shows that neither these rocks nor adjacent anorthosites and gneisses have been penetrated by large amounts of externally derived, hot CO2-H2O fluids during granulite facies metamorphism. This conclusion is supported by calculations of the effect of fluid volatilization and exchange and is also independently supported by petrologic and phase equilibria considerations. The data suggest that these rocks were not an open system during metamorphism; that fluid/rock ratios were in many instances between 0.0 and 0.1; that externally derived fluids, as well as fluids derived by metamorphic volatilization, rose along localized channels and were not pervasive; and thus that no single generalization can be applied to metamorphic fluid conditions in the Adirondacks. Analyses of 3 to 4 coexisting minerals from Adirondack marbles show that isotopic equilibrium was attained at the peak of granulite and upper amphibolite facies metamorphism. Thus the isotopic compositions of metamorphic fluids can be inferred from analyses of carbonates and fluid budgets can be constructed. Carbonates from the granulite facies are on average, isotopically similar to those from lower grade or unmetamorphosed limestones of the same age showing that no large isotopic shifts accompanied high grade metamorphism. Equilibrium calculations indicate that small decreases in ??18O, averaging 1 permil, result from volatilization reactions for Adirondack rock compositions. Additional small differences between amphibolite and granulite facies marbles are due to systematic lithologie differences. The range of Adirondack carbonate ??18O values (12.3 to 27.2) can be explained by the highly variable isotopic compositions of unmetamorphosed limestones in conjunction with minor 18O and 13C depletions caused by metamorphic volatilization suggesting that many (and possibly most) marbles have closely preserved their

  20. Late Quaternary vegetation and environments in the Verkhoyansk Mountains region (NE Asia) reconstructed from a 50-kyr fossil pollen record from Lake Billyakh

    NASA Astrophysics Data System (ADS)

    Müller, Stefanie; Tarasov, Pavel E.; Andreev, Andrei A.; Tütken, Thomas; Gartz, Steffi; Diekmann, Bernhard

    2010-08-01

    Here we present a detailed radiocarbon-dated 936 cm long pollen record from Lake Billyakh (65°17'N, 126°47'E; 340 m a.s.l.) situated in the western part of the Verkhoyansk Mountains, about 140 km south of the Arctic Circle. A set of 53 surface pollen samples representing tundra, cold deciduous forest and taiga was collected in northern and central Yakutia communities to verify the accuracy of the quantitative biome reconstruction method and to obtain a more precise attribution of the identified pollen taxa to the main regional biomes. The adjusted method is then applied to the pollen record from Lake Billyakh to gain a reconstruction of vegetation and environments since about 50.7 kyr BP. The results of the pollen analysis and pollen-based biome reconstruction suggest that herbaceous tundra and steppe communities dominated the area from 50.7 to 13.5 kyr BP. Relatively low pollen concentrations and high percentages of herbaceous pollen taxa (mainly Cyperaceae, Poaceae and Artemisia) likely indicate a reduced vegetation cover and/or lower pollen production. On the other hand, extremely low percentages of drought-tolerant taxa, such as Chenopodiaceae and Ephedra, and the constant presence of various mesophyllous herbaceous ( Thalictrum, Rosaceae, Asteraceae) and shrubby taxa ( Betula sect. Nanae/Fruticosae, Duschekia fruticosa, Salix) in the pollen assemblages prevent an interpretation of the last glacial environments around Lake Billyakh as extremely arid. The lowest pollen percentages of woody taxa and the highest values of Artemisia pollen attest that the 31-15 kyr BP period as the driest and coldest interval of the entire record. A relative high content of taxa representing shrub tundra communities and the presence of larch pollen recorded prior to 31 kyr and after 13.5 kyr BP likely indicate interstadial climate amelioration associated with the middle and latest parts of the last glacial. An increase in pollen percentages of herbaceous taxa around 12 kyr BP

  1. Climatological, hydrological and vegetation change for the past 15,000 years based upon a new network of high resolution lake sites in the Sierra Nevada and Unita Mountains

    NASA Astrophysics Data System (ADS)

    MacDonald, G. M.; Moser, K. A.; Porinchu, D. F.; Bloom, A.; Potito, A.; Petel, A.

    2004-12-01

    Instrumented lake and watershed climatic data along with lake sediment surface samples and cores are being used to develop and apply paleolimnological transfer functions to reconstruct climate change and ecosystem response in the eastern Sierra Nevada Mountains of California and the Unita Mountains of Utah. The selection of the two ranges provides a circum Great Basin perspective on natural climate variability in the western mountains. The California study sites are located in the eastern Sierra Nevada. Surface sediment samples and water samples have been analyzed from 57 lakes extending across an altitudinal gradient of 1360 m. Transfer functions that estimate water temperature, salinity and depth on the basis of lake diatom flora or chironomid fauna have been developed and published. Long cores have been obtained from 8 lakes that provide a transect from treeline down to the sagebrush dominated Great Basin. The lake records extend back between 9000 and 15,000 Cal yr BP. Pronounced warming of ~ 4.5 degrees C and development of modern conifer forest started by ~13,800 Cal yr BP. At ~11,000 Cal yr BP temperatures were as warm or warmer than today. High resolution analysis shows that the general glacial to interglacial warming was interrupted by a climatic reversal at approximately 13,000 Cal yr BP during which time summer temperatures at mid-elevation lakes cooled by 4 to 6 degrees C. There was a pronounced three part hydrological shift during this temperature reversal. The temperature reversal corresponds in timing with Younger Dryas Stadial typical of circum North Atlantic records. There was only a muted response to this episode at higher elevations and in the terrestrial vegetation. The cooling is synchronous with the Younger Dryas Stadial. Between ~8000 and 4000 Cal yr BP there was pronounced drying and lake drawdown at lower elevations. The period from 4000 Cal yr BP to the present has been typified by shifts between relatively moist conditions, like the

  2. Mitigating and Tracking Black Carbon Exposure at Schools in the Mountain View Corridor of Salt Lake City

    NASA Astrophysics Data System (ADS)

    Roberts, P. T.; Brown, S. G.; Vaughn, D.; DeWinter, J. L.

    2015-12-01

    Black carbon (BC) is a short lived climate forcer and is associated with human health effects. We measured BC inside and outside at four schools in Salt Lake City during two studies in 2011-2014. In addition, PM2.5 was measured indoor and outdoor at one school, and gaseous air toxics outdoor at one school. The schools are within 500 m of a planned major freeway, and two of them will adjoin the freeway. The objectives included determining the outdoor and indoor concentrations of BC, the likely sources of BC, and once the freeway is built, the change in ambient BC at the schools. We determined the current state of air quality outdoors at these schools, to provide baseline data for comparison when the major freeway is operational, and indoors as a baseline before installing improved filtration to reduce BC in classrooms. Using MATES IV cancer risk values, we found that diesel particulate matter, as indicated by ambient, outdoor BC measurements, was responsible for 84% of the cancer risk at the schools. The HVAC system was moderately effective at filtrating PM mass (73% reduction), but very poor at filtering BC (7%-34% reduction), indicating that air toxics risk is similar indoors and outdoors. Improved filtration devices could potentially mitigate this risk, and improved filtration systems have been recommended for the schools. Lastly, we used the difference in absorption at two Aethalometer channels to determine that the majority of BC (> 90%) during the spring through fall is from fossil fuel emissions.

  3. Glacial lake inventory and lake outburst potential in Uzbekistan.

    PubMed

    Petrov, Maxim A; Sabitov, Timur Y; Tomashevskaya, Irina G; Glazirin, Gleb E; Chernomorets, Sergey S; Savernyuk, Elena A; Tutubalina, Olga V; Petrakov, Dmitriy A; Sokolov, Leonid S; Dokukin, Mikhail D; Mountrakis, Giorgos; Ruiz-Villanueva, Virginia; Stoffel, Markus

    2017-03-16

    Climate change has been shown to increase the number of mountain lakes across various mountain ranges in the World. In Central Asia, and in particular on the territory of Uzbekistan, a detailed assessment of glacier lakes and their evolution over time is, however lacking. For this reason we created the first detailed inventory of mountain lakes of Uzbekistan based on recent (2002-2014) satellite observations using WorldView-2, SPOT5, and IKONOS imagery with a spatial resolution from 2 to 10m. This record was complemented with data from field studies of the last 50years. The previous data were mostly in the form of inventories of lakes, available in Soviet archives, and primarily included localized in-situ data. The inventory of mountain lakes presented here, by contrast, includes an overview of all lakes of the territory of Uzbekistan. Lakes were considered if they were located at altitudes above 1500m and if lakes had an area exceeding 100m(2). As in other mountain regions of the World, the ongoing increase of air temperatures has led to an increase in lake number and area. Moreover, the frequency and overall number of lake outburst events have been on the rise as well. Therefore, we also present the first outburst assessment with an updated version of well-known approaches considering local climate features and event histories. As a result, out of the 242 lakes identified on the territory of Uzbekistan, 15% are considered prone to outburst, 10% of these lakes have been assigned low outburst potential and the remainder of the lakes have an average level of outburst potential. We conclude that the distribution of lakes by elevation shows a significant influence on lake area and hazard potential. No significant differences, by contrast, exist between the distribution of lake area, outburst potential, and lake location with respect to glaciers by regions.

  4. Utah: Salt Lake City

    Atmospheric Science Data Center

    2014-05-15

    ... mountains surrounding Salt Lake City are renowned for the dry, powdery snow that results from the arid climate and location at the ... should be used with the red filter placed over your left eye. The canyons and peaks of the Uinta and Wasatch Mountains are ...

  5. 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

  6. Stereo Pair of Height as Color & Shaded Relief, New York State, Lake Ontario to Long Island

    NASA Technical Reports Server (NTRS)

    2000-01-01

    From Lake Ontario and the St. Lawrence River (at the top of the image) and extending to Long Island (at the bottom) this image shows the varied topography of eastern New York State and parts of Massachusetts, Connecticut, Pennsylvania and New Jersey. The high 'bumpy' area in the middle to top right is the southern and western Adirondack Mountains, a deeply eroded landscape that includes the oldest exposed rocks in the eastern U.S.

    On the left side is the Catskill Mountains, a part of the Appalachian Mountain chain, where river erosion has produced an intricate pattern of valleys. Between the Adirondacks and Catskills is a wide valley that contains the Mohawk River and the Erie Canal. On the northwest (top) of the Catskills are several long, narrow lakes, some of the Finger Lakes of central New York that were carved by the vast glacier that covered this entire image as recently as 18,000 years ago.

    The Hudson River runs along a straight valley from right center (near Glens Falls), widening out as it approaches New York City at the lower left on the image. The Connecticut River valley has a similar north-south trend further to the east (across the lower right corner of the image). The Berkshires are between the Hudson and Connecticut valleys. Closer to the coast are the more deeply eroded rocks of the area around New York City, where several resistant rock units form topographic ridges.

    This image product is derived from a preliminary SRTM elevation model, processed with preliminary navigation information from the Space Shuttle. Broad scale and fine detail distortions in the model seen here will be corrected in the final elevation model.

    This stereoscopic image was generated by first creating and combining a shaded relief image and a height as color image, both of which were derived from the elevation model. Large water bodies were then masked, and the result was then draped back over the elevation model. Two differing perspectives were then

  7. Anaglyph of Shaded Relief New York State, Lake Ontario to Long Island

    NASA Technical Reports Server (NTRS)

    2000-01-01

    From Lake Ontario and the St. Lawrence River (at the top of the image) and extending to Long Island (at the bottom) this image shows the varied topography of eastern New York State and parts of Massachusetts, Connecticut, Pennsylvania and New Jersey. The high 'bumpy' area in the middle to top right is the southern and western Adirondack Mountains, a deeply eroded landscape that includes the oldest exposed rocks in the eastern U.S.

    On the left side is the Catskill Mountains, a part of the Appalachian Mountain chain, where river erosion has produced an intricate pattern of valleys. Between the Adirondacks and Catskills is a wide valley that contains the Mohawk River and the Erie Canal. On the northwest (top) of the Catskills are several long, narrow lakes, some of the Finger Lakes of central New York that were carved by the vast glacier that covered this entire region as recently as 18,000 years ago.

    The Hudson River runs along a straight valley from right center (near Glens Falls), widening out as it approaches New York City at the lower left on the image. The Connecticut River valley has a similar north-south trend further to the east (across the lower right corner of the image). The Berkshires are between the Hudson and Connecticut valleys. Closer to the coast are the more deeply eroded rocks of the area around New York City, where several resistant rock units form topographic ridges.

    This image product is derived from a preliminary SRTM elevation model, processed with preliminary navigation information from the Space Shuttle. Broad scale and fine detail distortions in the model seen here will be corrected in the final elevation model.

    This anaglyph was generated by first creating a shaded relief image from the elevation data, masking the large water bodies, and draping the result back over the elevation model. Two differing perspectives were then calculated, one for each eye. When viewed through special glasses, the result is a vertically

  8. A 22 570-year record of vegetational and climatic change from Wenhai Lake in the Hengduan Mountains biodiversity hotspot, Yunnan, Southwest China

    NASA Astrophysics Data System (ADS)

    Yao, Y. F.; Song, X. Y.; Wortley, A. H.; Blackmore, S.; Li, C. S.

    2015-03-01

    The Hengduan Mountains, with their strong altitudinal vegetation zonation, form a biodiversity hotspot which offers the potential for comparison between sites in order to understand how this zonation arose and how it has responded to climate change and human impacts through time. This paper presents a 22 570-year pollen record of vegetational and climatic change based on a core 320 cm in depth collected from Wenhai Lake on Jade Dragon Snow Mountain, one of the highest peaks in the Hengduan Mountains region of Yunnan, Southwest China. From 22 570 to 21 140 cal yr BP, the vegetation was dominated by broad-leaved forest (comprising mainly Quercus, Betula and Castanopsis), accompanied by needle-leaved forest (mainly Pinus and Abies), indicating a rather cold and dry climate relative to the present followed by cold and wet conditions. In the period between 21 140 and 19 350 cal yr BP, the vegetation was still dominated by broad-leaved forest and needle-leaved forest as before but with a notable increase in Betula pollen and a sharp decrease in Quercus pollen, implying a relatively cold and dry climate with several fluctuations in humidity. The period 19 350 to 17 930 cal yr BP was a transition stage from broad-leaved forest to needle-leaved forest, with a dramatic decrease in Quercus pollen and a maximum reading for Abies pollen, reflecting the coldest and driest climate since 22 570 cal yr BP. The expansion in needle-leaved forest dominated by Pinus and Abies (22 570-17 930 cal yr BP) along with an increase of Betula might correspond to the Last Glacial Maximum (LGM; the start of the LGM perhaps occurred prior to the basal age of the core). Between 17 930 and 9250 cal yr BP, needle-leaved forest declined and broad-leaved forest began to increase at first, suggesting increases in temperature and humidity, while towards the end of the period, needle-leaved forest expanded and broad-leaved forest shrank, indicating a colder and drier climate, possibly corresponding to the

  9. History of atmospheric deposition of trace elements in lake sediments, ~1880 to 2007

    NASA Astrophysics Data System (ADS)

    Sarkar, Sayantan; Ahmed, Tanveer; Swami, Kamal; Judd, Christopher D.; Bari, Abdul; Dutkiewicz, Vincent A.; Husain, Liaquat

    2015-06-01

    We report measurements of 30 major and trace elements (TEs) in sediment cores from two high-altitude lakes, West Pine Pond (WPP), and Clear Pond (CP), in the Adirondack Mountains of New York State using inductively coupled plasma-mass spectrometry. The data are used to deduce atmospheric deposition histories of TEs over ~130 years. The cores were collected using a gravity corer, sliced, freeze dried, and ages determined using 210Pb and 137Cs techniques. TE data in WPP were supplemented with our earlier elemental carbon (EC) measurements. Lithophilic elements showed no systematic temporal pattern or any significant enrichment over their crustal abundances. Anthropogenic TEs exhibited distinct increases beginning ~1900, and peaked around 1920-1970, due apparently to energy-related emissions. Peak concentrations of most TEs, except Pb and Hg, were observed at ~1921 in WPP and ~1940s in CP. Concentration of Pb peaked in 1973 in both lakes and Hg only in CP at ~1965. Lead fluxes were reflective of historical smelter production and combustion of coal and leaded gasoline. Copper and zinc fluxes mimicked corresponding primary production, while EC fluxes followed the long-term trend for fossil and biofuel combustion. TE and EC flux trends were closely related to the growth of industrialization in the Central and Midwestern U.S. and changing fuel consumption patterns. Compared to peak values, the modern TE fluxes decreased by 25-85%, whereas EC decreased by 96%. Apparently, the regulations intended to control pollutant emissions have succeeded in reducing atmospheric concentrations of the species studied and have improved air quality.

  10. Mercury in Wetlands, Adirondack Region of New York State

    NASA Astrophysics Data System (ADS)

    Yavitt, J. B.; Kalicin, M.; Driscoll, C. T.; Newton, R.; Munson, R.

    2001-05-01

    Wetlands play a prominent role in the cycling of mercury by harboring bacteria that transform mercury into methyl mercury, a neurotoxin, and by having high concentrations of dissolved organic carbon (DOC) that interact with mercury transport. We are measuring total mercury and methyl mercury in vegetation, soil, surface water, and ground water in the Sunday Lake watershed, in which wetlands cover 274 ha of the 1340-ha watershed area. Three wetland types occur: (1) riparian wetlands adjacent to low-order streams that drain the upland forested watershed; (2) peat-forming wetlands dominated by Carex sedges; and, (3) low shrub, Sphagnum (bog moss) dominated peatlands. Total mercury concentrations in wetland ground waters were greater in the riparian wetland (10.6 ng/L) and in sites with shallow peat than deep peat, suggesting water moves more readily around the peat than through it. The highest rates of microbial activity occurred in the top 10-cm of the sedge-derived peat, presumably being fueled by the freshest organic matter, although there was no relationship between microbial activity and DOC. Microbial sulfate reduction, which can methylate inorganic mercury, occurred in sites closest to low-order streams, presumably being fueled by sulfate brought into wetlands in surface water. Sites located away from the stream had microbial methane production, where demethylation might be occurring. Overall the wetlands are the primary source of methyl mercury within the watershed, and we are measuring water flow pathways and microbial processes to learn more about wetland controls of mercury cycling in watersheds.

  11. 10. ELECTRICAL SWITCHING STATION FOR IRON MOUNTAIN BRINGS ELECTRICITY FROM ...

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

    10. ELECTRICAL SWITCHING STATION FOR IRON MOUNTAIN BRINGS ELECTRICITY FROM HOOVER DAM COMPLEX. - Iron Mountain Pump Plant, South of Danby Lake, north of Routes 62 & 177 junction, Rice, San Bernardino County, CA

  12. 8. IRON MOUNTAIN SHAFT ROOM TO UNIT #5 SHOWING TYPICAL ...

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

    8. IRON MOUNTAIN SHAFT ROOM TO UNIT #5 SHOWING TYPICAL ARRANGEMENT OF SHAFT AND PUMP IN COLORADO RIVER AQUEDUCT PUMPHOUSES. - Iron Mountain Pump Plant, South of Danby Lake, north of Routes 62 & 177 junction, Rice, San Bernardino County, CA

  13. Soil efflux and total emission rates of magmatic CO2 at the horseshoe lake tree kill, mammoth mountain, California, 1995-1999

    USGS Publications Warehouse

    Gerlach, T.M.; Doukas, M.P.; McGee, K.A.; Kessler, R.

    2001-01-01

    We report the results of eight soil CO2 efflux surveys by the closed circulation chamber method at the Horseshoe Lake tree kill (HLTK) - the largest tree kill on Mammoth Mountain. The surveys were undertaken from 1995 to 1999 to constrain total HLTK CO2 emissions and to evaluate occasional efflux surveys as a surveillance tool for the tree kills. HLTK effluxes range from 1 to > 10,000 g m -2 day -1 (grams CO2 per square meter per day); they are not normally distributed. Station efflux rates can vary by 7-35% during the course of the 8- to 16-h surveys. Disturbance of the upper 2 cm of ground surface causes effluxes to almost double. Semivariograms of efflux spatial covariance fit exponential or spherical models; they lack nugget effects. Efflux contour maps and total CO2 emission rates based on exponential, spherical, and linear kriging models of survey data are nearly identical; similar results are also obtained with triangulation models, suggesting that the kriging models are not seriously distorted by the lack of normal efflux distributions. In addition, model estimates of total CO2 emission rates are relatively insensitive to the measurement precision of the efflux rates and to the efflux value used to separate magmatic from forest soil sources of CO2. Surveys since 1997 indicate that, contrary to earlier speculations, a termination of elevated CO2 emissions at the HLTK is unlikely anytime soon. The HLTK CO2 efflux anomaly fluctuated greatly in size and intensity throughout the 1995-1999 surveys but maintained a N-S elongation, presumably reflecting fault control of CO2 transport from depth. Total CO2 emission rates also fluctuated greatly, ranging from 46 to 136 t day-1 (metric tons CO2 per day) and averaging 93 t day-1. The large inter-survey variations are caused primarily by external (meteorological) processes operating on time scales of hours to days. The externally caused variations can mask significant changes occurring at depth; a striking example is

  14. The origin of garnet in the anorthosite-charnockite suite of the Adirondacks

    USGS Publications Warehouse

    McLelland, J.M.; Whitney, P.R.

    1977-01-01

    Detailed analysis of textural and chemical criteria in rocks of the anorthosite-charnockite suite of the Adirondack Highlands suggests that development of garnet in silica-saturated rocks of the suite occurs according to the reaction: {Mathematical expression}, where ?? is a function of the distribution of Fe and Mg between the several coexisting ferromagnesian phases. Depending upon the relative amounts of Fe and Mg present, quartz may be either a reactant or a product. Using an aluminum-fixed reference frame, this reaction can be restated in terms of a set of balanced partial reactions describing the processes occurring in spatially separated domains within the rock. The fact that garnet invariably replaces plagioclase as opposed to the other reactant phases indicates that the aluminum-fixed model is valid as a first approximation. This reaction is univariant and produces unzoned garnet. It differs from a similar equation proposed by de Waard (1965) for the origin of garnet in Adirondack metabasic rocks, i.e. 6 Orthopyroxene+2 Anorthite = Clinopyroxene+Garnet+2 Quartz, the principle difference being that iron oxides (ilmenite and/or magnetite) are essential reactant phases in the present reactions. The product assemblage (garnet+clinopyroxene+plagioclase ?? orthopyroxene ?? quartz) is characteristic of the clinopyroxene-almandine subfacies of the granulite facies. ?? 1977 Springer-Verlag.

  15. Using Satellite Imagery to Assess Large-Scale Habitat Characteristics of Adirondack Park, New York, USA

    NASA Astrophysics Data System (ADS)

    McClain, Bobbi J.; Porter, William F.

    2000-11-01

    Satellite imagery is a useful tool for large-scale habitat analysis; however, its limitations need to be tested. We tested these limitations by varying the methods of a habitat evaluation for white-tailed deer ( Odocoileus virginianus) in the Adirondack Park, New York, USA, utilizing harvest data to create and validate the assessment models. We used two classified images, one with a large minimum mapping unit but high accuracy and one with no minimum mapping unit but slightly lower accuracy, to test the sensitivity of the evaluation to these differences. We tested the utility of two methods of assessment, habitat suitability index modeling, and pattern recognition modeling. We varied the scale at which the models were applied by using five separate sizes of analysis windows. Results showed that the presence of a large minimum mapping unit eliminates important details of the habitat. Window size is relatively unimportant if the data are averaged to a large resolution (i.e., township), but if the data are used at the smaller resolution, then the window size is an important consideration. In the Adirondacks, the proportion of hardwood and softwood in an area is most important to the spatial dynamics of deer populations. The low occurrence of open area in all parts of the park either limits the effect of this cover type on the population or limits our ability to detect the effect. The arrangement and interspersion of cover types were not significant to deer populations.

  16. WILSON MOUNTAINS WILDERNESS, COLORADO.

    USGS Publications Warehouse

    Bromfield, Calvin S.; Williams, Frank E.

    1984-01-01

    The Wilson Mountains Wilderness consists of about 68 sq mi in the San Miguel Mountains in southwestern Colorado. Based on a mineral survey two areas in the wilderness have a probable mineral-resource potential. One area is on the east margin of the area in the Trout Lake mining district, and the other is near the center of the area, the Mount Wilson mining district. Both areas have had a modest base and (or) precious metal production from narrow veins and have a probable potential for the occurrence of similar deposits. Of more significance is a probable mineral-resource potential for disseminated copper mineralization in the Mount Wilson mining district.

  17. Origin of coronas in metagabbros of the Adirondack mts., N. Y

    USGS Publications Warehouse

    Whitney, P.R.; McLelland, J.M.

    1973-01-01

    Metagabbros from two widely separated areas in the Adirondacks show development of coronas. In the Southern Adirondacks, these are cored by olivine which is enclosed in a shell of orthopyroxene that is partially, or completely, rimmed by symplectites consisting of clinopyroxene and spinel. Compositions of the corona phases have been determined by electron probe and are consistent with a mechanism involving three partial reactions, thus: (a) Olivine=Orthopyroxene+(Mg, Fe)++. (b) Plagioclase+(Mg, Fe)+++Ca++=Clinopyroxene+Spinel+Na+. (c) Plagioclase+(Mg, Fe)+++Na+=Spinel+more sodic plagioclase+Ca++. Reaction (a) occurs in the inner shell of the corona adjacent to olivine; reaction (b) in the outer shell; and (c) in the surrounding plagioclase, giving rise to the spinel clouding which is characteristic of the plagioclase in these rocks. Alumina and silica remain relatively immobile. These reactions, when balanced, can be generalized to account for the aluminous nature of the pyroxenes and for changing plagioclase composition. Summed together, the partial reactions are equivalent to: (d) Olivine + Anorthite = Aluminous orthopyroxene + Aluminous Clinopyroxene + Spinel (Kushiro and Yoder, 1966). In the Adirondack Highlands, coronas between olivine and plagioclase commonly have an outer shell of garnet replacing the clinopyroxene/spinel shell. The origin of the garnet can also be explained in terms of three partial reactions: (e) Orthopyroxene+Ca++=Clinopyroxene+(Mg, Fe)++. (f) Clinopyroxene+Spinel+Plagioclase+(Mg, Fe)++=Garnet+Ca+++Na+. (g) Plagioclase+(Mg, Fe)+++Na+=Spinel + more sodic plagioclase+Ca++. These occur in the inner and outer corona shell and the surrounding plagioclase, respectively, and involve the products of reactions (a)-(d). Alumina and silica are again relatively immobile. Balanced, and generalized to account for aluminous pyroxenes and variable An content of plagioclase, they are equivalent to: (h) Orthopyroxene+Anorthite+Spinel=Garnet (Green and

  18. Historical Changes in the Ecosystem Condition of a Small Mountain Lake over the Past 60 Years as Revealed by Plankton Remains and Daphnia Ephippial Carapaces Stored in Lake Sediments

    PubMed Central

    Ohtsuki, Hajime; Awano, Tamotsu; Tsugeki, Narumi K.; Ishida, Seiji; Oda, Hirotaka; Makino, Wataru; Urabe, Jotaro

    2015-01-01

    To examine if changes in species composition of a plankton community in the past due to anthropogenic activities can be clarified in lakes without any monitoring data, we analyzed genetically ephippial carapaces of Daphnia with plankton remains stored in the bottom sediments of Lake Hataya Ohunma in Japan. In the lake, abundance of most plankton remains in the sediments was limited and TP flux was at low levels (2–4 mg/m2/y) before 1970. However TP flux increased two-fold during the period from 1980s to 1990s. In parallel with this increase, abundance of most plankton remains increased although abundance of benthic testate amoebae’s remains decreased, indicating that the lake trophic condition had changed from oligo- to mesotrophic for the past 60 years. According to cluster analysis, the stratigraphic sediments were divided into two periods with different features of the phytoplankton composition. Chronological comparison with events in the watershed suggested that eutrophication occurred because of an increase in visitors to the watershed and deposition of atmospheric dust. In this lake more than 50% of resting eggs produced by Daphnia over the past 60 years hatched. However, genetic analysis of the ephippial carapaces (remains) showed that the Daphnia population was originally composed of D. dentifera but that D. galeata, or its hybrid with D. dentifera, invaded and increased the population density when the lake was eutrophied. Subsequently, large D. pulex established populations in the 1980s when largemouth bass were anonymously introduced. These results indicated that the Lake Hataya Ohunma plankton community underwent significant changes despite the fact that there were no notable changes in land cover or land use in the watershed. Since increases in atmospheric deposition and release of fish have occurred in many Japanese lakes, the changes in the plankton community described here may be widespread in these lakes. PMID:25757090

  19. A generalized garnet-forming reaction for metaigneous rocks in the Adirondacks

    USGS Publications Warehouse

    McLelland, J.M.; Whitney, P.R.

    1980-01-01

    A generalized reaction is presented to account for garnet formation in a variety of Adirondack metaigneous rocks. This reaction, which is the sum of five partial reactions written in aluminum-fixed frames of reference, is given by: 4(y+1+w)Anorthite+4 k(y+1+2 w)Olivine +4(1-k)(y+1+2 w)Fe-oxide+(8(y+1) -4 k(y+1+2 w))Orthopyroxene = 2(y+1)Garnet +2(y+1+2 w)Clinopyroxene+4 wSpinel where y is a function of plagioclase composition, k refers to the relative amounts of olivine and Fe-oxide participating in the reaction, and w is a measure of silicon mobility. When mass balanced for Mg and Fe, this reaction is found to be consistent with analyzed mineral compositions in a wide range of Adirondack metaigneous rocks. The reaction applies equally well whether the garnets were formed directly from the rectants given above or went through an intermadiate stage involving the formation of spinel, orthopyroxene, and clinopyroxene. The actual reactions which have produced garnet in both undersaturated and quartz-bearing rocks are special cases of the above general reaction. The most important special cases appear to be those in which the reactants include either olivine alone (k=1) or Fe-oxide alone (k=0). Silicon is relatively immobile (w =2) in olivine bearing, magnesium-rich rocks (k???1), and this correlates with the increased intensity in spinel clouding of plagioclase in these rocks. Silicon mobility apparently increases in the more iron-rich rocks, which also tend to contain clear or lightly clouded plagioclase. In all the rocks studied the most common composition of metamorphic plagioclase is close to An33 (i.e., y=1). Plagioclase of lower anorthite content may be too sodic to participate in garnet formation at the P-T conditions involved. ?? 1980 Springer-Verlag.

  20. Climate and Geomorphic Risks in High-Mountain Environments

    NASA Astrophysics Data System (ADS)

    Huggel, Christian; Kääb, Andreas; Schneider, Jean

    2010-03-01

    Glacier Hazards, Permafrost Hazards, and Glacier Lake Outburst Floods in Mountain Areas: Processes, Assessment, Prevention, Mitigation; Vienna, Austria, 10-13 November 2009; Recent atmospheric warming is profoundly affecting high-mountain environments around the world. Glaciers are thinning and retreating, new and often unstable lakes are forming at glacier margins, other lakes are suddenly draining, and permafrost is degrading. These changes pose serious hazards to people and property in mountain valleys. Several tens of thousands of people were killed by landslides, floods, and debris flows from high-mountain regions during the twentieth century, and there is concern that such events will increase as temperatures warm through the 21st century.

  1. Salt Lake City, Utah

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Salt Lake City, Utah, will host the 2002 Winter Olympic Games. The city is located on the southeastern shore of the Great Salt Lake and sits to the west of the Wasatch Mountains, which rise more than 3,500 meters (10,000 feet) above sea level. The city was first settled in 1847 by pioneers seeking relief from religious persecution. Today Salt Lake City, the capital of Utah, is home to more than 170,000 residents. This true-color image of Salt Lake City was acquired by the Enhanced Thematic Mapper Plus (ETM+), flying aboard Landsat 7, on May 26, 2000. The southeastern tip of the Great Salt Lake is visible in the upper left of the image. The furrowed green and brown landscape running north-south is a portion of the Wasatch Mountains, some of which are snow-capped (white pixels). The greyish pixels in the center of the image show the developed areas of the city. A number of water reservoirs can be seen east of the mountain range. Salt Lake City International Airport is visible on the northwestern edge of the city. About 20 miles south of the airport is the Bingham Canyon Copper Mine (tan pixels), the world's largest open pit excavation. See also this MODIS image of Utah. Image courtesy NASA Landsat7 Science Team and USGS Eros Data Center

  2. Organic contaminants in mountains.

    PubMed

    Daly, Gillian L; Wania, Frank

    2005-01-15

    The study of organic contaminants at high altitudes is motivated by the potential risk that they pose to humans living in, or depending on resources derived from, mountains and to terrestrial and aquatic ecosystems in alpine areas. Mountains are also ideal settings to study contaminant transport and behavior along gradients of climate and surface cover. Information on organic contaminants in mountains is compiled from the literature and synthesized, with a focus on atmospheric transport and deposition, contaminant dynamics in alpine lakes and aquatic organisms, and concentration differences with altitude. Diurnal mountain winds, in connection with enhanced deposition at higher elevations caused by low temperatures and high precipitation rates, conspire to make mid-latitude mountains become convergence zones for selected persistent organic chemicals. In particular, the more volatile constituents of contaminant mixtures seem to become enriched, relative to the less volatile constituents at higher altitudes. For selected contaminants, concentration inversions (i.e., concentrations that increase with elevation) have been observed. A notable difference between cold trapping in high latitudes and high altitudes is the likely importance of precipitation. High rates of snow deposition in mid- and high-latitude mountains may lead to a large contaminant release during snowmelt. Regions above the tree line often have little capacity to retain the released contaminants, suggesting the potential for a highly dynamic contaminant fate situation during the snow-free season with significant revolatilization and runoff. The chemical and environmental factors that control the orographic cold trapping of organic contaminants should be examined further by measuring and comparatively interpreting concentration gradients along several mountain slopes with widely different characteristics. Future efforts should further focus on the bioaccumulation and potential effects of contaminants in

  3. I. Stratigraphy, chemistry, K-Ar dating, and paleomagnetism of the Nine Hill Tuff, California-Nevada. II. Miocene/Oligocene ash-flow tuffs of Seven Lakes Mountain, California-Nevada. III. Improved calibration methods and error estimates for

    SciTech Connect

    Deino, A.L.

    1985-01-01

    I. The Nine Hill Tuff is a widespread mid-Tertiary ash-flow tuff, exposed intermittently from the central Sierra Nevada Foothills in California to the edge of the Carson Sink in Nevada. Maximum thicknesses of 250-300 m are attained near Carson City and Lemon Valley north of Reno, while the tuff in the Sierra Nevada is usually < 20 m thick. A reconnaissance paleomagnetic study was conducted to provide an independent chick on correlations of the Nine Hill Tuff in the Sierra Nevada proposed on the basis of K-Ar dating, geochemistry, textures, and mineralogical data. II. Oligocene/Miocene ash-flow tuffs of Seven Lakes Mountain (40 55'N, 120 W), located southeast of Honey Lake, California, have a composite maximum thickness of 645 m. Nine cooling units, which are further defined in the dissertation, have been recognized, ranging in K-Ar age from 23.0 to 30.5 m.y. III. Improved accuracy, precision, and error estimates in /sup 40/K-/sup 40/Ar dating can be achieved by employing a zero-age curve which quantitatively predicts the total non-radiogenic /sup 40/Ar component of a gas sample measured on a given argon extraction-mass spectrometer system.

  4. Preliminary analysis of the role of lake basin morphology on the modern diatom flora in the Ruby Mountains and East Humboldt Range, Nevada, USA

    USGS Publications Warehouse

    Starratt, Scott W.

    2014-01-01

    As paleolimnologists, we often look at the world through a 5-cm-diameter hole in the bottom of a lake, and although a number of studies have shown that a single core in the deepest part of a lake does not necessarily reflect the entire diatom flora, time and money often limit our ability to collect more than one core from a given site. This preliminary study is part of a multidisciplinary research project to understand Holocene climate variability in alpine regions of the Great Basin, and ultimately, to compare these high elevation records to the better studied pluvial records from adjacent valleys, in this case, the Ruby Valley.

  5. Concentration and flux of solutes from snow and forest floor during snowmelt in the West-Central Adirondack region of New York

    USGS Publications Warehouse

    Rascher, C.M.; Driscoll, C.T.; Peters, N.E.

    1987-01-01

    Decreases in pH and increases in the concentration of Al and NO3- have been observed in surface waters draining acid-sensitive regions in the northeastern U.S. during spring snowmelt. To assess the source of this acidity, we evaluated solute concentrations in snowpack, and in meltwater collected from snow and forest floor lysimeters in the west-central Adirondack Mountains of New York during the spring snowmelt period, 29 March through 15 April 1984. During the initial phase of snowmelt, ions were preferentially leached from the snowpack resulting in elevated concentrations in snowmelt water (e.g. H+ = 140 ??eq.l-1; NO42- = 123 ??eq.l-1; SO3- = 160 ??eq.l-1). Solute concentrations decreased dramatically within a few days of the initial melt (< 50 ??eq.l-1). The concentrations of SO42- and NO3- in snowpack and snowmelt water were similar, whereas NO-3 in the forest floor leachate was at least two times the concentration of SO42-. Study results suggest that the forest floor was a sink for snowmelt inputs of alkalinity, and a net source of H+, NO3-, dissolved organic carbon, K+ and Al inputs to the mineral soil. The forest floor was relatively conservative with respect to snowmelt inputs of Ca2+, SO42- and Cl-. These results indicate that mineralization of N, followed by nitrification in the forest floor may be an important process contributing to elevated concentrations of H+ and NO3- in streams during the snowmelt period. ?? 1987 Martinus Nijhoff/Dr W. Junk Publishers.

  6. Integrated Lake-Watershed Acidification Study (ILWAS): contributions to the international conference on the ecological impact of acid precipitation

    SciTech Connect

    Not Available

    1981-05-01

    The Integrated Lake-Watershed Acidification Study (ILWAS) was initiated to study and detail lake acidification processes for three lake watershed basins in the Adirondack Park region of New York. The three basins (Woods, Sagamore, and Panther), receive similar amounts of acid deposition yet observable pH values for the lakes are very dissimilar indicating unequal acid neutralizing capacities among the watersheds. This volume contains a compilation of seven papers. Relevant topics include: a characterization of the geology, hydrology, limnology and vegetation of the three study sites, an analysis of acid precipitation quality and quantity, the effects of vegetative canopy, the effects of snowmelt, the effects of winter lake stratification, comparison of heavy metal transport, examination of acidic sources other than direct precipitation, assessment of lake acidification during spring thaw and integration of all acidification components with a mathematical model.

  7. Lake oxygen isotopes as recorders of North American Rocky Mountain hydroclimate: Holocene patterns and variability at multi-decadal to millennial time scales

    USGS Publications Warehouse

    Anderson, Lesleigh; Max Berkelhammer,; Barron, John A.; Steinman, Byron A.; Finney, Bruce P.; Abbott, Mark B.

    2016-01-01

    Lake sediment oxygen isotope records (calcium carbonate-δ18O) in the western North American Cordillera developed during the past decade provide substantial evidence of Pacific ocean–atmosphere forcing of hydroclimatic variability during the Holocene. Here we present an overview of 18 lake sediment δ18O records along with a new compilation of lake water δ18O and δ2H that are used to characterize lake sediment sensitivity to precipitation-δ18O in contrast to fractionation by evaporation. Of the 18 records, 14 have substantial sensitivity to evaporation. Two records reflect precipitation-δ18O since the middle Holocene, Jellybean and Bison Lakes, and are geographically positioned in the northern and southern regions of the study area. Their comparative analysis indicates a sequence of time-varying north–south precipitation-δ18O patterns that is evidence for a highly non-stationary influence by Pacific ocean–atmosphere processes on the hydroclimate of western North America. These observations are discussed within the context of previous research on North Pacific precipitation-δ18O based on empirical and modeling methods. The Jellybean and Bison Lake records indicate that a prominent precipitation-δ18O dipole (enriched-north and depleted-south) was sustained between ~ 3.5 and 1.5 ka, which contrasts with earlier Holocene patterns, and appears to indicate the onset of a dominant tropical control on North Pacific ocean–atmosphere dynamics. This remains the state of the system today. Higher frequency reversals of the north–south precipitation-δ18O dipole between ~ 2.5 and 1.5 ka, and during the Medieval Climate Anomaly and the Little Ice Age, also suggest more varieties of Pacific ocean–atmosphere modes than a single Pacific Decadal Oscillation (PDO) type analogue. Results indicate that further investigation of precipitation-δ18O patterns on short (observational) and long (Holocene) time scales is needed to improve our understanding of the

  8. Lake oxygen isotopes as recorders of North American Rocky Mountain hydroclimate: Holocene patterns and variability at multi-decadal to millennial time scales

    NASA Astrophysics Data System (ADS)

    Anderson, Lesleigh; Berkelhammer, Max; Barron, John A.; Steinman, Byron A.; Finney, Bruce P.; Abbott, Mark B.

    2016-02-01

    Lake sediment oxygen isotope records (calcium carbonate-δ18O) in the western North American Cordillera developed during the past decade provide substantial evidence of Pacific ocean-atmosphere forcing of hydroclimatic variability during the Holocene. Here we present an overview of 18 lake sediment δ18O records along with a new compilation of lake water δ18O and δ2H that are used to characterize lake sediment sensitivity to precipitation-δ18O in contrast to fractionation by evaporation. Of the 18 records, 14 have substantial sensitivity to evaporation. Two records reflect precipitation-δ18O since the middle Holocene, Jellybean and Bison Lakes, and are geographically positioned in the northern and southern regions of the study area. Their comparative analysis indicates a sequence of time-varying north-south precipitation-δ18O patterns that is evidence for a highly non-stationary influence by Pacific ocean-atmosphere processes on the hydroclimate of western North America. These observations are discussed within the context of previous research on North Pacific precipitation-δ18O based on empirical and modeling methods. The Jellybean and Bison Lake records indicate that a prominent precipitation-δ18O dipole (enriched-north and depleted-south) was sustained between ~ 3.5 and 1.5 ka, which contrasts with earlier Holocene patterns, and appears to indicate the onset of a dominant tropical control on North Pacific ocean-atmosphere dynamics. This remains the state of the system today. Higher frequency reversals of the north-south precipitation-δ18O dipole between ~ 2.5 and 1.5 ka, and during the Medieval Climate Anomaly and the Little Ice Age, also suggest more varieties of Pacific ocean-atmosphere modes than a single Pacific Decadal Oscillation (PDO) type analogue. Results indicate that further investigation of precipitation-δ18O patterns on short (observational) and long (Holocene) time scales is needed to improve our understanding of the processes that drive

  9. Late glacial aridity in southern Rocky Mountains

    SciTech Connect

    Davis, O.K.; Pitblado, B.L.

    1995-09-01

    While the slopes of the present-day Colorado Rocky Mountains are characterized by large stands of subalpine and montane conifers, the Rockies of the late glacial looked dramatically different. Specifically, pollen records suggest that during the late glacial, Artemisia and Gramineae predominated throughout the mountains of Colorado. At some point between 11,000 and 10,000 B.P., however, both Artemisia and grasses underwent a dramatic decline, which can be identified in virtually every pollen diagram produced for Colorado mountain sites, including Como Lake (Sangre de Cristo Mountains), Copley Lake and Splains; Gulch (near Crested Butte), Molas Lake (San Juan Mountains), and Redrock Lake (Boulder County). Moreover, the same pattern seems to hold for pollen spectra derived for areas adjacent to Colorado, including at sites in the Chuska Mountains of New Mexico and in eastern Wyoming. The implications of this consistent finding are compelling. The closest modem analogues to the Artemisia- and Gramineae-dominated late-glacial Colorado Rockies are found in the relatively arid northern Great Basin, which suggests that annual precipitation was much lower in the late-glacial southern Rocky Mountains than it was throughout the Holocene.

  10. Juvenile Middle Proterozoic crust in the Adirondack Highlands, Grenville province, northeastern North America

    SciTech Connect

    Daly, J.S. ); McLelland, J.M. )

    1991-02-01

    Nd isotope data indicate that minimal amounts of significantly older crust have contributed to the genesis of the oldest (ca. 1.3-13.5 Ga) plutons in the Adirondack Highlands. These are magmatic arc tonalites with positive initial {epsilon}{sub Nd} values and Sm-Nd depleted mantle model ages (t{sub DM}) that are within 70 m.y. of the time of their crystallization. Granitoids of the anorthosite-mangerite-charnockite-granite suite, dated at 1,156-1,134 Ma, as well as the 1,100-1,050 Ma plutons, associated with the Ottawan phase of the Grenvillian orogenic cycle, also have positive initial {epsilon}{sub Nd} values and t{sub DM} ages similar to the tonalites. Derivation of both groups of granitoids by crustal melting of the magmatic arc is consistent with the available isotopic and geochemical data. Juvenile late Middle Proterozoic crust that formed during or just prior to the Grenville cycle appears to dominate the southwestern Grenville province as well as the Grenville inliers to the south. In contrast, most of the contiguous Grenville province in Canada comprises largely reworked older crust.

  11. Sedimentology of basal Potsdam sandstone in Adirondack border region, New York, southeastern Ontario, and southwestern Quebec

    SciTech Connect

    McRae, L.E.; Johnson, G.D.

    1986-05-01

    Field evidence supports the relatively widespread presence of nonmarine facies within the basal Potsdam formation of the Adirondack border areas of northern New York, southeastern Ontario, and southwestern Quebec. Detailed observations of areal extent, analysis of sedimentary structures and paleocurrent directions, and petrographic studies have been combined with the paleomagnetic determination of the temporal relationships of these strata to establish depositional patterns and facies trends within basal Potsdam units. Four distinct nonmarine lithofacies have been identified: massive matrix-supported conglomerate, stratified framework-supported conglomerate, conglomerate-arkose, and pebble conglomerate-arkose fining-upward sequences, interpreted to represent debris flows, proximal gravelly braided-stream deposits, intermediate to distal gravelly braided-stream deposits, and proximal sandy braided-stream deposits, respectively. Facies of eolian or possibly tidal, and shallow marine origin have also been identified at the base of the Potsdam sequence. Most basal Potsdam sediments are compositionally and texturally immature, derived directly from the crystalline detritus of the extensively weathered Precambrian surface and regoliths that may have locally developed on the craton. The desert-like environment of the Precambrian surface allowed for rapid transport and deposition of relatively unweathered sediments and the subsequent construction of a braided alluvial plain system. Field relations and evidence derived from consideration of the paleomagnetic properties in five localities of fine-grained alluvium suggest that terrestrial Potsdam deposition in the Early and Middle Cambrian largely preceded the marine transgression that deposited the thick, shallow marine units typifying most of the Potsdam sequence.

  12. U-Pb zircon geochronology and evolution of some Adirondack meta-igneous rocks

    NASA Technical Reports Server (NTRS)

    Mclelland, J. M.

    1988-01-01

    An update was presented of the recent U-Pb isotope geochronology and models for evolution of some of the meta-igneous rocks of the Adirondacks, New York. Uranium-lead zircon data from charnockites and mangerites and on baddeleyite from anorthosite suggest that the emplacement of these rocks into a stable crust took place in the range 1160 to 1130 Ma. Granulite facies metamorphism was approximately 1050 Ma as indicated by metamorphic zircon and sphene ages of the anorthosite and by development of magmatitic alaskitic gneiss. The concentric isotherms that are observed in this area are due to later doming. However, an older contact metamorphic aureole associated with anorthosite intrusion is observed where wollastonite develops in metacarbonates. Zenoliths found in the anorthosite indicate a metamorphic event prior to anorthosite emplacement. The most probable mechanism for anorthosite genesis is thought to be ponding of gabbroic magmas at the Moho. The emplacement of the anorogenic anorthosite-mangerite-charnockite suite was apparently bracketed by compressional orogenies.

  13. Development of LANDSAT Derived Forest Cover Information for Integration into Adirondack Park GIS

    NASA Technical Reports Server (NTRS)

    Curran, R. P.; Banta, J. S.

    1982-01-01

    Based upon observed changes in timber harvest practices partially attributable to forest biomass removable for energy supply purposes, the Adirondack Park Agency began in 1979 a multi-year project to implement a digital geographic information system (GIS). An initial developmental task was an inventory of forest cover information and analysis of forest resource change and availability. While developing the GIS, a pilot project was undertaken to evaluate the usefulness of LANDSAT derived land cover information for this purpose, and to explore the integration of LANDSAT data into the GIS. The prototype LANDSAT analysis project involved: (1) the use of both recent and historic data to derive land cover information for two dates; and (2) comparison of land cover over time to determine quantitative and geographic changes. The "recent data," 1978 full foliage data over portions of four LANDSAT scenes, was classified, using ground truth derived training samples in various forested and non-forested categories. Forested categories include the following: northern hardwoods, pine, spruce-fir, and pine plantation, while nonforested categories include wet-conifer, pasture, grassland, urban, exposed soil, agriculture, and water.

  14. Hydraulic and biochemical gradients limit wetland mercury supply to an Adirondack stream

    USGS Publications Warehouse

    Bradley, Paul M.; Burns, Douglas A.; Harvey, Judson; Journey, Celeste; Brigham, Mark E.; Murray, Karen

    2016-01-01

    Net fluxes (change between upstream and downstream margins) for water, methylmercury (MeHg), total mercury (THg), dissolved organic carbon (DOC), and chloride (Cl) were assessed twice in an Adirondack stream reach (Sixmile Brook, USA), to test the hypothesized importance of wetland-stream hydraulic and chemical gradients as fundamental controls on fluvial mercury (Hg) supply. The 500 m study reach represented less than 4% of total upstream basin area. During a snowmelt high-flow event in May 2009 surface water, DOC, and chloride fluxes increased by 7.1±1.3%, 8.0±1.3%, and 9.0±1.3%, respectively, within the reach, demonstrating that the adjacent wetlands are important sources of water and solutes to the stream. However, shallow groundwater Hg concentrations lower than in the surface water limited groundwater-surface water Hg exchange and no significant changes in Hg (filtered MeHg and THg) fluxes were observed within the reach despite the favorable hydraulic gradient. In August 2009, the lack of significant wetland-stream hydraulic gradient resulted in no net flux of water or solutes (MeHg, THg, DOC, or Cl) within the reach. The results are consistent with the wetland-Hg-source hypothesis and indicate that hydraulic and chemical gradient (direction and magnitude) interactions are fundamental controls on the supply of wetland Hg to the stream.

  15. Chemical variations within a metagabbro, N. W. Adirondack lowlands, N. Y

    SciTech Connect

    Von Derau, G.D. Jr.; Van Brocklin, M.F. . Geology Dept.)

    1993-03-01

    A metagabbro located in the N.W. Adirondack lowlands has been examined in order to study the chemical changes that occur from the edge of the body into the core. Samples were collected from within a mine adit starting near the contact of the country rock and going into the metagabbro for a distance of 65 feet. The country rock contains an assemblage of alkali feldspar, plagioclase, quartz, biotite, apatite and magnetite. The metagabbro contains an assemblage of plagioclase, hornblende, clinopyroxene, biotite, quartz, sphene, apatite and opaques. Chemical data show a decrease of SiO[sub 2] and K[sub 2]O from the edge of the metagabbro towards the center, and an increase in CaO, Fe[sub 2]O[sub 3], MgO, TiO[sub 2], P[sub 2]O[sub 5], Ni, V, and Cr[sub 2]O[sub 3]. The Al[sub 2]O[sub 3], and Na[sub 2]O content remain nearly constant. Hand samples stained with sodium cobaltinitrite also reflect decreasing K[sub 2]O towards the core of the body. These chemical gradations may be due to metasomatism, assimilation of country rock or true compositional zoning during crystallization of an alkali-rich gabbro.

  16. Sulfite-reducing clostridia in the sediment of a high mountain lake (Laguna Grande, Gredos, Spain) as indicators of fecal pollution.

    PubMed

    Robles, S; Rodríguez, J M; Granados, I; Guerrero, M C

    2000-09-01

    We studied the vertical distribution of sulfite-reducing clostridia in the sediment of a Spanish high-mountain lagoon (Laguna Grande de Gredos, central Spain), with optimal sediment characteristics (temperature < 20 degrees C) to maintain spores without growing. This allowed us to assess the original numbers of sulfite-reducing clostridia endospores settled, without postdepositional growing. Sulfite-reducing clostridia are normal inhabitants of the intestinal microbiota of humans and other mammals. These microorganisms may form endospores, which allow the bacteria to survive in almost any habitat, either terrestrial or aquatic, waiting for favorable conditions for growth. Sulfite-reducing clostridia could be suitable indicators of past human pollution because they have a great longevity in natural habitats and they cannot multiply at temperatures below 20 degrees C or in the presence of O2. We found a great increase in the numbers of clostridia (expressed as colony-forming units per gram [CFU/g] of dry weight of sediment) since the 1970s, which reflects the rise of human pressure caused by the practice of outdoor activities. Clostridia CFU/g rose dramatically after the faulty operation of the depuration system of a mountain refuge built close to the lagoon. We compared the vertical distribution of clostridia CFU/g from Laguna Grande sediments with those from a neighbor lagoon (Laguna Cimera), which showed less tourist pressure and no direct disposal of sewage. Finally, we agree with the usefulness of the numbers of sulfite-reducing clostridia as indicators of past pollution.

  17. 3. OVERALL VIEW OF DEER LAKE AND UPRIGHT OUTLET GATE ...

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

    3. OVERALL VIEW OF DEER LAKE AND UPRIGHT OUTLET GATE WHEEL, STEM AND STEM GUIDE, LOOKING NORTH - High Mountain Dams in Upalco Unit, Deer Lake Dam, Ashley National Forest, 5.8 miles North of Swift Creek Campground, Mountain Home, Duchesne County, UT

  18. A New Twist on the Seasonality of Nitrate Retention and Release in Adirondack Watersheds

    NASA Astrophysics Data System (ADS)

    Lawrence, G. B.; Ross, D. S.; Sutherland, J. W.; Nierzwicki-Bauer, S.; Boylen, C.

    2004-12-01

    Release of nitrate to surface waters in the Northeast has a distinct seasonality that is generally explained by high retention from plant uptake during the growing season, and low retention during the non-growing season, when biological demand is low and soil- water flux is elevated in the absence of transpiration. In the Adirondack region of New York, the highest rates of release, which consistently occur during spring snowmelt, are considered to be the result of nitrate accumulation in the soil and snowpack over the winter. This explanation implies that plants out compete nitrifying bacteria for available ammonium during the growing season. Biweekly and automated high-flow sampling over five years in two tributaries of Buck Creek, in the western Adirondacks, however, has revealed inconsistencies with the conventional view of nitrate retention and release. Although low concentrations of nitrate were measured in stream water during the growing season, concentrations were lowest each year in mid October (near the completion of leaf drop) in the North tributary, and were either the lowest or second lowest each year in mid October in the South tributary. Furthermore, concentrations of nitrate in both watersheds remained elevated throughout the snowmelt periods despite sustained high flows. For example, the concentration in the South tributary on April 9th, 2001, (the initial stage of snowmelt) was 76 micromoles per liter, and on April 24th (following two of the three largest flow events over the 5 years of sampling), was 82 micromoles per liter. Flushing of nitrate stored in the soil over the winter would result in a peak concentration in the stream that would be followed by a rapid decrease. To explain these results we hypothesize a three-way competition that includes heterotrophic non-nitrifying bacteria, as well as plants and autotrophic nitrifying bacteria. Leaf drop in the fall provides a large input of labile carbon with a high C to N ratio (>20) that favors

  19. Charnockites and granites of the western Adirondacks, New York, USA: a differentiated A-type suite

    USGS Publications Warehouse

    Whitney, P.R.

    1992-01-01

    Granitic rocks in the west-central Adirondack Highlands of New York State include both relatively homogeneous charnockitic and hornblende granitic gneisses (CG), that occur in thick stratiform bodies and elliptical domes, and heterogeneous leucogneisses (LG), that commonly are interlayered with metasedimentary rocks. Major- and trace-element geochemical analyses were obtained for 115 samples, including both types of granitoids. Data for CG fail to show the presence of more than one distinct group based on composition. Most of the variance within the CG sample population is consistent with magmatic differentiation combined with incomplete separation of early crystals of alkali feldspar, plagioclase, and pyroxenes or amphibole from the residual liquid. Ti, Fe, Mg, Ca, P, Sr, Ba, and Zr decrease with increasing silica, while Rb and K increase. Within CG, the distinction between charnockitic (orthopyroxene-bearing) and granitic gneisses is correlated with bulk chemistry. The charnockites are consistently more mafic than the hornblende granitic gneisses, although forming a continuum with them. The leucogneisses, while generally more felsic than the charnockites and granitic gneisses, are otherwise geochemically similar to them. The data are consistent with the LG suite being an evolved extrusive equivalent of the intrusive CG suite. Both CG and LG suites are metaluminous to mildly peraluminous and display an A-type geochemical signature, enriched in Fe, K, Ce, Y, Nb, Zr, and Ga and depleted in Ca, Mg, and Sr relative to I- and S-type granites. Rare earth element patterns show moderate LREE enrichment and a negative Eu anomaly throughout the suite. The geochemical data suggest an origin by partial melting of biotite- and plagioclase-rich crustal rocks. Emplacement occurred in an anorogenic or post-collisional tectonic setting, probably at relatively shallow depths. Deformation and granulite-facies metamorphism with some partial melting followed during the Ottawan phase

  20. Appalachian Mountains

    Atmospheric Science Data Center

    2014-05-15

    article title:  Appalachian Mountains     View Larger Image Multi-angle views of the Appalachian Mountains, March 6, 2000 . The true-color image at left is a ... location:  United States region:  Eastern United States Order:  3 ...

  1. Appalachian Mountains

    Atmospheric Science Data Center

    2014-05-15

    article title:  Aerosols over the Appalachian Mountains     View ... Imaging SpectroRadiometer (MISR) acquired these views of the Appalachian Mountains on March 6, 2000. The image at left is a downward-looking ... location:  United States region:  Eastern United States Order:  2 ...

  2. Landscape level estimate of lands and waters impacted by road runoff in the Adirondack Park of New York State.

    PubMed

    Regalado, Sean A; Kelting, Daniel L

    2015-08-01

    Road runoff is understood to be a significant stressor in terrestrial and aquatic ecosystems, yet the effects of this stressor are poorly understood at large spatial scales. We developed an efficient method for estimating the spatial impact of road runoff on lands and waters over large geographic areas and then applied our methodology to the 2.4 million ha Adirondack Park in New York State. We used TauDEM hydrologic modeling and a series of ESRI GIS processes to delineate surface flow downslope of paved roads, illustrating the potential movement of pollutants originating from paved roads through the USGS 10 m DEM topography. We then estimated the land and surface water areas, number of water bodies, and total stream length potentially impacted by road runoff from paved roads. We found that as much as 11% of land area, 77% of surface water area, 1/3 of the water bodies, and 52% of stream length in the Adirondack Park may be impacted by road runoff. The high degree of hydrologic association between paved roads and the lands and waters of this region strongly suggests that the environmental impacts of road runoff should be evaluated along with other regional stressors currently being studied. Being able to estimate the spatial impact of road runoff is important for designing monitoring programs that can explicitly monitor this stressor while also providing opportunities to understand the interaction of multiple environmental stressors.

  3. Calcium Sulfate in Atacama Desert Basalt: A Possible Analog for Bright Material in Adirondack Basalt, Gusev Crater

    NASA Technical Reports Server (NTRS)

    Sutter, B.; Golden, D. C.; Amundson, R.; Chong-Diaz, G.; Ming, D. W.

    2007-01-01

    The Atacama Desert in northern Chile is one of the driest deserts on Earth (< 2mm/y). The hyper-arid conditions allow extraordinary accumulations of sulfates, chlorides, and nitrates in Atacama soils. Examining salt accumulations in the Atacama may assist understanding salt accumulations on Mars. Recent work examining sulfate soils on basalt parent material observed white material in the interior vesicles of surface basalt. This is strikingly similar to the bright-white material present in veins and vesicles of the Adirondack basalt rocks at Gusev Crater which are presumed to consist of S, Cl, and/or Br. The abundance of soil gypsum/anhydrite in the area of the Atacama basalt suggested that the white material consisted of calcium sulfate (Ca-SO4) which was later confirmed by SEM/EDS analysis. This work examines the Ca-SO4 of Atacama basalt in an effort to provide insight into the possible nature of the bright material in the Adirondack basalt of Gusev Crater. The objectives of this work are to (i) discuss variations in Ca-SO4 crystal morphology in the vesicles and (ii) examine the Ca-SO4 interaction(s) with the basalt interior.

  4. Sustainability and economics: The Adirondack Park experience, a forest economic-ecological model, and solar energy policy

    NASA Astrophysics Data System (ADS)

    Erickson, Jon David

    The long-term sustainability of human communities will depend on our relationship with regional environments, our maintenance of renewable resources, and our successful disengagement from nonrenewable energy dependence. This dissertation investigates sustainability at these three levels, following a critical analysis of sustainability and economics. At the regional environment level, the Adirondack Park of New York State is analyzed as a potential model of sustainable development. A set of initial and ongoing conditions are presented that both emerge from and support a model of sustainability in the Adirondacks. From these conditions, a clearer picture emerges of the definition of regional sustainability, consequences of its adoption, and lessons from its application. Next, an economic-ecological model of the northern hardwood forest ecosystem is developed. The model integrates economic theory and intertemporal ecological concepts, linking current harvest decisions with future forest growth, financial value, and ecosystem stability. The results indicate very different economic and ecological outcomes by varying opportunity cost and ecosystem recovery assumptions, and suggest a positive benefit to ecological recovery in the forest rotation decision of the profit maximizing manager. The last section investigates the motives, economics, and international development implications of renewable energy (specifically photovoltaic technology) in rural electrification and technology transfer, drawing on research in the Dominican Republic. The implications of subsidizing a photovoltaic market versus investing in basic research are explored.

  5. Is there biomagnification of organochlorines in a Rocky Mountain aquatic food web?

    SciTech Connect

    Campbell, L.M.; Schindler, D.W.; Kidd, K.; Donald, D.D.; Muir, D.

    1995-12-31

    In 1991--92, 14 lakes in the Canadian Rocky Mountains were surveyed for organochlorine contamination (PCBs, DDT isomers, toxaphene, and other pesticides) of water and lake trout. Lake trout from Bow Lake, near the Continental Divide, in Banff National Park, contained particularly high concentrations of organochlorines, notably toxaphene, in their tissue compared to other mountain lake trout populations. The hypothesis that the high degree of contamination in fish is caused by biomagnification is being tested by analysis of lake trout (Salveninus namaycush), mountain whitefish (Propsopium williamsoni), benthic invertebrates, and zooplankton for organochlorine compounds and stable nitrogen isotopes (15N/14N). Fish, invertebrates, sediments and water collected from Bow Lake in 1994 were all found to contain organochlorines, and the authors are investigating the apparent patterns of contamination present. The possibility that contaminants deposited in past decades on the glaciers that feed Bow Lake contributes to the high values is also being examined.

  6. Stone Mountain

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This color image taken by the panoramic camera onboard the Mars Exploration Rover Opportunity shows the part of the rock outcrop dubbed Stone Mountain at Meridiani Planum, Mars. Scientists are examining Stone Mountain with the instruments on the rover's instrument deployment device, or 'arm,' in search of clues about the composition of the rock outcrop. [figure removed for brevity, see original site] A Patch of Stone (Figure credit: NASA/JPL/Cornell/USGS)

    The colorless square in this color image of the martian rock formation called Stone Mountain is one portion of the rock being analyzed with tools on the Mars Exploration Rover Opportunity's instrument deployment device, or 'arm.' The square area is approximately 3 centimeters (1.2 inches) across. Stone Mountain is located within the rock outcrop on Meridiani Planum, Mars. The image was taken by the rover's panoramic camera.

  7. Reacidification modeling and dose calculation procedures for calcium-carbonate-treated lakes

    SciTech Connect

    Scheffe, R.D.

    1987-01-01

    Two dose calculation models and a reacidification model were developed and applied to two Adirondack acid lakes (Woods Lake and Cranberry Pond) that were treated with calcite during May 30-31, 1985 as part of the EPRI-funded Lake Acidification Mitigation Project. The first dose model extended Sverdrup's (1983) Lake Liming model by incorporating chemical equilibrium routines to eliminate empirical components. The model simulates laboratory column water chemistry profiles (spatially and temporally) and dissolution efficiencies fairly well; however, the model predicted conservative dissolution efficiencies for the study lakes. Time-series water chemistry profiles of the lakes suggest that atmospheric carbon dioxide intrusion rate was far greater than expected and enhanced dissolution efficiency. Accordingly, a second dose model was developed that incorporated ongoing CO/sub 2/ intrusion and added flexibility in the handling of solid and dissolved species transport. This revised model simulated whole-lake water chemistry throughout the three week dissolution period. The Acid Lake Reacidification Model (ALaRM) is a general mass-balance model developed for the temporal prediction of the principal chemical species in both the water column and sediment pore water of small lakes and ponds.

  8. Map showing areas with potential for talc deposits in the Gravelly, Greenhorn, and Ruby ranges and the Henrys Lake Mountains of southwestern Montana

    USGS Publications Warehouse

    Van Gosen, Bradley S.; Berg, Richard B.; Hammarstrom, Jane M.

    1998-01-01

    For the last several years, Montana has been the leading talc producing state in the United States (U.S. Geological Survey, 1996). For example, in 1992 Montana supplied about 40 percent of the U.S. mine production of talc (Virta, 1992). All of this production has come from the large deposits of high purity talc in the southwestern part of the state. All Montana talc is currently (1997) extracted from four mines, each within the study area of this map—the open pit operations of the Treasure State, Regal, and Yellowstone mines and the underground operation of the Beaverhead mine (see map numbers 1-4 on list and map to the left). The related mineral chlorite is mined at the Antler mine, located nearby, but outside of the study area in the Highland Mountains. Montana talc has at least two market advantages: (1) some deposits are very large and near surface, allowing economic mining by open pit methods; and (2) the deposits are of high purity and lack tremolite or other amphibole mineral contaminants (such as absestos) that occur in some other talc-rich deposits. Talc from southwest Montana is used in ceramics, paint, paper, plastics, cosmetics, rubber, roofing, flooring, caulking, and agricultural applications. The talc is also used in the processes of recycling paper and plastics. Talc was first discovered in the early 1900's at the present site of the Yellowstone mine (Perry, 1948, p. 9). Modest production began in 1942 from shallow pits and adits, supplying steatite (massive, compact, high-purity) talc that was used to make ceramic insulators. The southwest Montana talc industry grew to become a significant part of the region's economy; this history is described by Perry (1948), Olson (1976), and Berg (1997). Exploration and development are likely to continue for the foreseeable future for several reasons: (1) mines are active in the area at present and an infrastructure for talc processing exists; (2) large changes in domestic and export talc markets are not

  9. Plagioclase zonation styles in hornblende gabbro inclusions from Little Glass Mountain, Medicine Lake volcano, California: Implications for fractionation mechanisms and the formation of composition gaps

    USGS Publications Warehouse

    Brophy, J.G.; Dorais, M.J.; Donnelly-Nolan, J.; Singer, B.S.

    1997-01-01

    The rhyolite of Little Glass Mountain (73-74% SiO2) is a single eruptive unit that contains inclusions of quenched andesite liquid (54-61% SiO2) and partially crystalline cumulate hornblende gabbro (53-55% SiO2). Based on previous studies, the quenched andesite inclusions and host rhyolite lava are related to one another through fractional crystallization and represent an example of a fractionation-generated composition gap. The hornblende gabbros represent the cumulate residue associated with the rhyolite-producing and composition gap-forming fractionation event. This study combines textural (Nomarski Differential Interference Contrast, NDIC, imaging), major element (An content) and trace element (Mg, Fe, Sr, K, Ti, Ba) data on the style of zonation of plagioclase crystals from representative andesite and gabbro inclusions, to assess the physical environment in which the fractionation event and composition gap formation took place. The andesite inclusions (54-61% SiO2) are sparsely phyric with phenocrysts of plagioclase, augite and Fe-oxide??olivine, +/-orthopyroxene, +/-hornblende set within a glassy to crystalline matrix. The gabbro cumulates (53-55% SiO2) consist of an interconnected framework of plagioclase, augite, olivine, orthopyroxene, hornblende and Fe-oxide along with highly vesicular interstitial glass (70-74% SiO2). The gabbros record a two-stage crystallization history of plagioclase + olivine + augite (Stage I) followed by plagioclase+orthopyroxene + hornblende + Fe-oxide (Stage II). Texturally, the plagioclase crystals in the andesite inclusions are characterized by complex, fine-scale oscillatory zonation and abundant dissolution surfaces. Compositionally (An content) the crystals are essentially unzoned from core-to-rim. These features indicate growth within a dynamic (convecting?), reservoir of andesite magma. In contrast, the plagioclase crystals in the gabbros are texturally smooth and featureless with strong normal zonation from An74 at the

  10. Metal and proton toxicity to lake zooplankton: a chemical speciation based modelling approach.

    PubMed

    Stockdale, Anthony; Tipping, Edward; Lofts, Stephen; Fott, Jan; Garmo, Oyvind A; Hruska, Jakub; Keller, Bill; Löfgren, Stefan; Maberly, Stephen C; Majer, Vladimir; Nierzwicki-Bauer, Sandra A; Persson, Gunnar; Schartau, Ann-Kristin; Thackeray, Stephen J; Valois, Amanda; Vrba, Jaroslav; Walseng, Bjørn; Yan, Norman

    2014-03-01

    The WHAM-FTOX model quantifies the combined toxic effects of protons and metal cations towards aquatic organisms through the toxicity function (FTOX), a linear combination of the products of organism-bound cation and a toxic potency coefficient for each cation. We describe the application of the model to predict an observable ecological field variable, species richness of pelagic lake crustacean zooplankton, studied with respect to either acidification or the impacts of metals from smelters. The fitted results give toxic potencies increasing in the order H(+) < Al < Cu < Zn < Ni. In general, observed species richness is lower than predicted, but in some instances agreement is close, and is rarely higher than predictions. The model predicts recovery in agreement with observations for three regions, namely Sudbury (Canada), Bohemian Forest (Czech Republic) and a subset of lakes across Norway, but fails to predict observed recovery from acidification in Adirondack lakes (USA).

  11. Estimating groundwater inflow and leakage outflow for an intermontane lake with a structurally complex geology: Georgetown Lake in Montana, USA

    NASA Astrophysics Data System (ADS)

    Shaw, Glenn D.; Mitchell, Katie L.; Gammons, Christopher H.

    2016-12-01

    Stable isotopes of the water molecule (δ18O and δD) for groundwater, lake water, streams, and precipitation were coupled with physical flux measurements to investigate groundwater-lake interactions and to establish a water balance for a structurally complex lake. Georgetown Lake, a shallow high-latitude high-elevation lake, is located in southwestern Montana, USA. The lake is situated between two mountain ranges with highlands primarily to the east and south of the lake and a lower valley to the west. An annual water balance and (δ18O and δD) isotope balance were used to quantify annual groundwater inflows of 2.5 × 107 m3/year and lake leakage outflows of 1.6 × 107 m3/year. Roughly, 57% of total inflow to the lake is from groundwater, and 37% of total outflow at Georgetown Lake is groundwater. Stable isotopes of groundwater and springs around the lake and surrounding region show that the east side of the lake contains meteoric water recharged annually from higher mountain sources, and groundwater discharge to the lake occurs through this region. However, springs located in the lower western valley and some of the surrounding domestic wells west of the lake show isotopic enrichment indicative of strong to moderate evaporation similar to Georgetown Lake water. This indicates that some outflowing lake water recharges groundwater through the underlying west-dipping bedrock in the region.

  12. Specific ultra-violet absorbance as an indicator measurement of merucry sources in an Adirondack River basin

    USGS Publications Warehouse

    Burns, Douglas A.; Aiken, George R.; Bradley, Paul M.; Journey, Celeste; Schelker, Jakob

    2013-01-01

    The Adirondack region of New York has been identified as a hot spot where high methylmercury concentrations are found in surface waters and biota, yet mercury (Hg) concentrations vary widely in this region. We collected stream and groundwater samples for Hg and organic carbon analyses across the upper Hudson River, a 493 km2 basin in the central Adirondacks to evaluate and model the sources of variation in filtered total Hg (FTHg) concentrations. Variability in FTHg concentrations during the growing seasons (May-Oct) of 2007-2009 in Fishing Brook, a 66-km2 sub-basin, was better explained by specific ultra-violet absorbance at 254 nm (SUVA254), a measure of organic carbon aromaticity, than by dissolved organic carbon (DOC) concentrations, a commonly used Hg indicator. SUVA254 was a stronger predictor of FTHg concentrations during the growing season than during the dormant season. Multiple linear regression models that included SUVA254 values and DOC concentrations could explain 75 % of the variation in FTHg concentrations on an annual basis and 84 % during the growing season. A multiple linear regression landscape modeling approach applied to 27 synoptic sites across the upper Hudson basin found that higher SUVA254 values are associated with gentler slopes, and greater riparian area, and lower SUVA254 values are associated with an increasing influence of open water. We hypothesize that the strong Hg?SUVA254 relation in this basin reflects distinct patterns of FTHg and SUVA254 that are characteristic of source areas that control the mobilization of Hg to surface waters, and that the seasonal influence of these source areas varies in this heterogeneous basin landscape.

  13. Application of a continuous distribution model for proton binding by humic acids extracted from acidic lake sediments

    SciTech Connect

    Rhea, J.R.; Young, T.C. )

    1987-01-01

    The proton binding characteristics of humic acids extracted from the sediments of Cranberry Pond, an acidic water body located in the Adirondack Mountain region of New York State, were explored by the application of a nultiligand distribution model. The model characterizes a class of proton binding sites by mean log K values and the standard deviations of log K values and the mean. Mean log K values and their relative abundances were determined directly from experimental titration data. The model accurately predicts the binding of protons by the humic acids for pH values in the range 3.5 to 10.0.

  14. Application of a continuous distribution model for proton binding by humic acids extracted from acidic lake sediments

    NASA Astrophysics Data System (ADS)

    Rhea, James R.; Young, Thomas C.

    1987-10-01

    The proton binding characteristics of humic acids extracted from the sediments of Cranberry Pond, an acidic water body located in the Adirondack Mountain region of New York State, were explored by the application of a multiligand distribution model. The model characterizes a class of proton binding sites by mean log K values and the standard deviations of log K values about the mean. Mean log K values and their relative abundances were determined directly from experimental titration data. The model accurately predicts the binding of protons by the humic acids for pH values in the range 3.5 to 10.0.

  15. Geohydrological Implications of Climate Change on Water Resource Development

    DTIC Science & Technology

    1979-05-01

    50 inches in the extreme eastern part in the Adirondacks . Annual precipitation over the region averages 31 inches, but areas east of the lakes...into the Adirondack Mountains. Major structural features include a deep sedimentary basin centered under Michigan, a shallow sedimentary plain bordering...shortages would exist, salinity of surface water would increase and mining of ground water (with accompanying mining subsidence, faulting and salt water

  16. Current and historical deposition of PBDEs, pesticides, PCBs, and PAHs to Rocky Mountain National Park

    EPA Science Inventory

    An analytical method was developed for the trace analysis of 98 semi-volatile organic compounds (SOCs) in remote, high elevation lake sediment. Sediment cores from Lone Pine Lake (West of the Continental Divide) and Mills Lake (East of the Continental Divide) in Rocky Mountain Na...

  17. Habitat Suitability Index Models: Lake trout (exclusive of the Great Lakes)

    USGS Publications Warehouse

    Marcus, Michael D.; Hubert, Wayne A.; Anderson, Stanley H.

    1984-01-01

    The lake trout is an important commercial and sport fish in North America. In the Central Rocky Mountain regi on, 1ake trout are common ly referred to as "mackinaw". There is good evidence that lake trout should be called "1 ake charr" (Morton 1980). No subspecies of lake trout is presently recognized (Robins et al. 1980). The species, however, has extreme variability throughout its range, making it difficult to draw general conclusions about its biology (Martin and Olver 1980).

  18. Quaternary ledoyoms in the mountains of southern Siberia

    NASA Astrophysics Data System (ADS)

    Rudoy, A. N.

    2012-04-01

    In the 1930s V.P. Nekhoroshev identified intermontane depressions in the Altai mountains that he suspected o be completely filled by glaciers from the surrounding mountains at the time of maximum glaciation. He called such depressions "ledoyoms," or "ice bodies." Some basins already contained lakes when the glaciers advanced into them; in others the valley glaciers impounded lakes when they advanced into the basins. The advancing glaciers in this case became floating or grounded "shelf" glaciers at their lower ends, and some—singly or with neighboring glaciers—armored completely the surface of the "catch lakes." Thus, ledoyoms may develop as: (1) ice only, with no related lake. (2) catch lakes, with both glaciers and related lakes. (3) aufeis ledoyoms; (4) ice-dammed lakes lacking glacial ice cover. During the last glacial maximum some Altai lakes were covered with glacial ice for thousands of years. They consisted of a thick lens of lake water covered by lake ice, aufeis, glacier ice, snow and firn, and became independent centers of glaciation with subradial ice outlets. Possible modern analogs are the subglacial lakes under 3-4 km of glacier ice at Dome B, Dome C, and Vostok Station in Eastern Antarctica.

  19. Geographic Analysis of Alaska Lake Districts

    NASA Astrophysics Data System (ADS)

    Arp, C. D.; Jones, B. M.; Zimmerman, C. E.

    2007-12-01

    The state of Alaska has over 400,000 lakes greater than 0.01 km2 in surface area covering approximately 3.3% of the landscape. As in most lake-rich regions, these lakes are unevenly distributed on the landscape. So in order to better understand how lakes are organized on the landscape and relate this geographic organization to other climatologic, geologic, and biogeographic characteristics, we analyzed the spatial distribution of Alaska lakes. Using a combination of numerical abundance and surface-area extent of lakes, we selected lake density thresholds to identify and delineate 22 lake districts in Alaska. The total area of these 22 lakes districts occupy 16% of Alaska, yet encompass 64% of lakes and 76% of lake surface-area. The three largest lake districts are associated with the Yukon-Kuskokwin Delta, the Northern Arctic Coastal Plain, and the mountain front of the Alaskan Range on the Alaska Peninsula. Interestingly, these largest lake districts are covered by >17% lakes, while most of the smaller lake districts we identified have <10% lake cover. Of the remaining smaller lake districts, 9 are associated with mountain fronts or intermountain basins, 4 are associated with coastal plains, 3 are associated with floodplains and deltas, and 3 occur in high-elevation or mountain terrain. The highest numerical lake densities occur at deltas, while relatively lower densities occur in mountainous areas where individual lakes are often larger in surface area and likely volume. Comparison of these lake districts were made to permafrost distribution, glacial history, lithology, watershed position, and regional hydrologic budgets and regimes to better understand where lake-rich regions occur, why, and how they might change in the future. Ten of the 22 lake districts occur in areas dominated by continuous permafrost, 6 occur in areas of discontinuous or sporadic permafrost, and the other 6 occur in regions without perennially frozen soils. The majority of lake districts

  20. Lake Life.

    ERIC Educational Resources Information Center

    Ohrn, Deborah Gore, Ed.

    1993-01-01

    This quarterly publication of the State Historical Society of Iowa features articles and activities for elementary school students. This summer issue focuses on the topic of lake life. The issue includes the following features: (1) "Where the Lakes Are Map"; (2) "Letter from the Lake"; (3) "Lake People"; (4)…

  1. Lake Sarez, Tajikistan

    NASA Technical Reports Server (NTRS)

    2002-01-01

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

  2. New explorations along the northern shores of Lake Bonneville

    USGS Publications Warehouse

    Oviatt, Charles G.; Miller, D.M.

    1997-01-01

    This field trip begins in Salt Lake City and makes a clockwise circuit of Great Salt Lake, with primary objectives to observe stratigraphie and geomorphic records of Lake Bonneville. Stops include Stansbury Island, Puddle Valley, gravel pits at Lakeside and the south end of the Hogup Mountains, several stops in Curlew Valley and Hansel Valley, and a final stop at the north end of Great Salt Lake east of the Promontory Mountains. Stratigraphie observations at gravel-pit and natural exposures will be linked to interpretations of lake-level change, which were caused by climate change. Evidence of paleoseismic and volcanic activity will be discussed at several sites, and will be tied to the lacustrine stratigraphic record. The trip provides an overview of the history of Lake Bonneville and introduces participants to some new localities with excellent examples of Lake Bonneville landforms and stratigraphy.

  3. 32. Otter Lake Dam. View from downstream show how the ...

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

    32. Otter Lake Dam. View from downstream show how the dam blends into its environment. Looking east-northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  4. 130. Julian Price Memorial Park. Fortyseven acre Julian Price Lake ...

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

    130. Julian Price Memorial Park. Forty-seven acre Julian Price Lake created by an impoundment. Looking west. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  5. Mercury Inputs, Outputs, Cycling, and Ambient Concentrations under the Forest Canopy in the Adirondacks of New York

    NASA Astrophysics Data System (ADS)

    Choi, H.; Holsen, T.

    2009-12-01

    This study investigated mercury inputs, outputs, cycling, and the interactions between deposition, emissions and atmospheric conditions in the Huntington Forest of the Adirondacks, New York. Continuous speciated mercury concentrations of gaseous elemental Hg (GEM), reactive gaseous Hg (RGM), and particulate Bound Hg (PBM) were made from June 2006 to May 2007. The average concentrations of GEM, RGM, and PBM were 1.4 ± 0.4 ng m-3, 1.8 ± 2.2 pg m-3, and 3.2 ± 3.7 pg m-3, respectively. A hybrid receptor modeling technique (potential source contribution function (PSCF)) was used with the speciated Hg concentrations to identify possible Hg sources. Major Hg sources that have a potential to contribute high Hg concentrations observed in the Adirondacks were found to be Pennsylvania, West Virginia, Ohio, Kentucky, Texas, Indiana, and Missouri. The volume-weighted mean (VWM) total Hg concentration in throughfall (Dec. 2004 to Dec. 2006) (6.6 ng L-1) was higher than in precipitation (4.9 ng L-1), while the total cumulative Hg flux in throughfall (12.0 µg m-2) was similar to precipitation (11.6 µg m-2). The emission flux of GEM from the forest floor measured using a polycarbonate dynamic flux chamber (DFC) was highest in spring, and summer, and lowest in winter. The yearly estimated Hg inputs into the forest canopy include throughfall (6.5 g m-2 year-1), litterfall (18.3 g m-2 year-1), and dry deposition during leaf-off periods (0.4g m-2 year-1). The yearly estimated Hg outputs from the forest canopy include emission from the forest floor (7.0g m-2 year-1), soil water (0.6 g m-2 year-1), and Hg loss via evaporation or overland flow during snow melt (1.0 g m-2 year-1). Litterfall represented the most significant input of Hg to this forest ecosystem. Based on this mass balance, 16.6 g m-2 of Hg is accumulating in the forest floor every year.

  6. 75 FR 65613 - Withdrawal of Notice for Preparation of an Environmental Impact Statement for the Pine Mountain...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ... Statement for the Pine Mountain Dam & Lake Project, AR AGENCY: Department of the Army, U.S. Army Corps of...) is withdrawing its intent to prepare an Environmental Impact Statement (EIS) for the Pine Mountain... . SUPPLEMENTARY INFORMATION: The Pine Mountain Dam project was authorized for construction by Congress in...

  7. Origin of biotite-hornblende-garnet coronas between oxides and plagioclase in olivine metagabbros, Adirondack region, New York

    USGS Publications Warehouse

    Whitney, P.R.; McLelland, J.M.

    1982-01-01

    Complex multivariant reactions involving Fe-Ti oxide minerals, plagioclase and olivine have produced coronas of biotite, hornblende and garnet between ilmenite and plagioclase in Adirondack olivine metagabbros. Both the biotite (6-10% TiO2) and the hornblende (3-6% TiO2) are exceptionally Titanium-rich. The garnet is nearly identical in composition to the garnet in coronas around olivine in the same rocks. The coronas form in two stages: (a) Plagioclase+Fe-Ti Oxides+Olivine+water =Hornblende+Spinel+Orthopyroxene??Biotite +more-sodic Plagioclase (b) Hornblende+Orthopyroxene??Spinel+Plagioclase =Garnet+Clinopyroxene+more-sodic Plagioclase The Orthopyroxene and part of the clinopyroxene form adjacent to olivine. Both reactions are linked by exchange of Mg2+ and Fe2+ with the reactions forming pyroxene and garnet coronas around olivine in the same rocks. The reactions occur under granulite fades metamorphic conditions, either during isobaric cooling or with increasing pressure at high temperature. ?? 1983 Springer-Verlag.

  8. Lake Tahoe

    EPA Pesticide Factsheets

    Information on the Lake Tahoe watershed, EPA's protection efforts, water quality issues, effects of climate change, Lake Tahoe Total Maximum Daily Load (TMDL), EPA-sponsored projects, list of partner agencies.

  9. LAKE ELEANOR ROADLESS AREA, CALIFORNIA.

    USGS Publications Warehouse

    Huber, Donald F.; Cather, Eric E.

    1984-01-01

    The Lake Eleanor Roadless Area occupies an area of about 22. 3 sq mi in the Trinity Alps of the Klamath Mountains, 14-28 mi north-northeast of Weaverville, California. Mining began in the Trinity Alps about 1850 and has continued intermittently since then. There is no record of mining activity in the Lake Eleanor Roadless Area, but placer and lode mining occurred nearby. On the basis of mineral surveys the area has little promise for the occurrence of metallic, nonmetallic, or energy resources.

  10. Potential for acid precipitation damage to lakes of the Sierra Nevada, California

    SciTech Connect

    Harte, J.; Holdren, J.; Tonnesson, K.

    1983-04-01

    One of the areas of California potentially sensitive to acidic deposition is the Sierra Nevada, located along the eastern boundary. A report on sensitive areas in North America identifies the Sierra as a region characterized by poorly buffered soils and granite based lakes. The subalpine and alpine lakes in this region share many of the characteristics of lakes adversely affected by acid deposition in other parts of the US and the world. For this investigation selected subalpine lakes of the western slope of the Sierra were chosen for study, to establish baseline water quality which would allow for the identification of chemical and biological changes due to acidic deposition. It was then attempted to simulate the ecosystem stress of increased acidic deposition, particularly in the form of snowmelt, on these systems by performing microcosm experiments in the laboratory. These experiments were particularly concerned with recording changes in concentrations of micronutrients which might be leached from lake sediments with increasing acidification. This phenomenon is particularly important to study in the light of finds on the importance of aluminum leaching in the northeast which was led to toxic effects of biota in Adirondack lakes. 10 references, 3 figures, 1 table.

  11. 2. EAGLE MOUNTAIN SWITCHYARD. EAGLE MOUNTAIN PUMP PLANT CAN BE ...

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

    2. EAGLE MOUNTAIN SWITCHYARD. EAGLE MOUNTAIN PUMP PLANT CAN BE SEEN THROUGH SWITCHYARD IN BACKGROUND. 165MM LENS. - Eagle Mountain Pump Plant, Ten miles north of Route 10, southeast of Eagle Mountain, Eagle Mountain, Riverside County, CA

  12. 129. Julian Price Memorial Park. Price Lake Dam. A concrete ...

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

    129. Julian Price Memorial Park. Price Lake Dam. A concrete slab bridge crosses the top of the dam impounding a forty-seven acre lake. Looking west. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  13. Bathymetry and temperature of some glacial lakes in Wyoming

    PubMed Central

    Leopold, Luna B.

    1980-01-01

    On the west flank of the Wind River Mountains, Wyoming, are several large lakes occupying glacially scoured depressions dammed by terminal moraines. Fremont, Willow, and New Fork Lakes, having maximal depths of 185, 85, and 62 m, respectively, are not only deep, but in 1970-1978 they had no measurable coliform. They have exceptionally low values of total dissolved solids; Fremont Lake has only 12.8 mg/liter, probably the second most dilute large lake in coterminus United States. Summer mixing is restricted to the uppermost 10 m, below which the lakes are essentially isothermal at the maximum density temperature, about 3.9°C. PMID:16592797

  14. Bathymetry and temperature of some glacial lakes in Wyoming.

    PubMed

    Leopold, L B

    1980-04-01

    On the west flank of the Wind River Mountains, Wyoming, are several large lakes occupying glacially scoured depressions dammed by terminal moraines. Fremont, Willow, and New Fork Lakes, having maximal depths of 185, 85, and 62 m, respectively, are not only deep, but in 1970-1978 they had no measurable coliform. They have exceptionally low values of total dissolved solids; Fremont Lake has only 12.8 mg/liter, probably the second most dilute large lake in coterminus United States. Summer mixing is restricted to the uppermost 10 m, below which the lakes are essentially isothermal at the maximum density temperature, about 3.9 degrees C.

  15. Transient Tsunamis in Lakes

    NASA Astrophysics Data System (ADS)

    Couston, L.; Mei, C.; Alam, M.

    2013-12-01

    A large number of lakes are surrounded by steep and unstable mountains with slopes prone to failure. As a result, landslides are likely to occur and impact water sitting in closed reservoirs. These rare geological phenomena pose serious threats to dam reservoirs and nearshore facilities because they can generate unexpectedly large tsunami waves. In fact, the tallest wave experienced by contemporary humans occurred because of a landslide in the narrow bay of Lituya in 1958, and five years later, a deadly landslide tsunami overtopped Lake Vajont's dam, flooding and damaging villages along the lakefront and in the Piave valley. If unstable slopes and potential slides are detected ahead of time, inundation maps can be drawn to help people know the risks, and mitigate the destructive power of the ensuing waves. These maps give the maximum wave runup height along the lake's vertical and sloping boundaries, and can be obtained by numerical simulations. Keeping track of the moving shorelines along beaches is challenging in classical Eulerian formulations because the horizontal extent of the fluid domain can change over time. As a result, assuming a solid slide and nonbreaking waves, here we develop a nonlinear shallow-water model equation in the Lagrangian framework to address the problem of transient landslide-tsunamis. In this manner, the shorelines' three-dimensional motion is part of the solution. The model equation is hyperbolic and can be solved numerically by finite differences. Here, a 4th order Runge-Kutta method and a compact finite-difference scheme are implemented to integrate in time and spatially discretize the forced shallow-water equation in Lagrangian coordinates. The formulation is applied to different lake and slide geometries to better understand the effects of the lake's finite lengths and slide's forcing mechanism on the generated wavefield. Specifically, for a slide moving down a plane beach, we show that edge-waves trapped by the shoreline and free

  16. Mountains: An Overview.

    ERIC Educational Resources Information Center

    Byers, Alton; Gilligan, Nancy; Golston, Syd; Linville, Rex

    1999-01-01

    Introduces the lessons from "Mountain: A Global Resource" that were developed by the National Council for the Social Studies (NCSS) and The Mountain Institute for use by NCSS members and their students. Provides an overview that introduces the mountains, mountain cultures, historical perceptions, and the geographical importance of…

  17. Geochemical studies of mafic and other low silica, Precambrian intrusive rocks in the Adirondack lowlands, New York

    SciTech Connect

    Antibus, J.; Carl, J.D. . Dept. of Geology)

    1993-03-01

    Mafic metaigneous rocks in the Adirondack Lowlands include gabbros, amphibolites and diorites that are associated with, and hard to distinguish from, a host of dark colored, low-silica, alkali feldspar-bearing rocks that include syenogabbros, syenites and monzonites. All rocks intrude metasedimentary and metavolcanic host rocks and occur as isolated, pre- to syn-metamorphic bodies, generally with elongate, sheet-like form. Some occur within or marginal to deformation zones. Lacking are the massive igneous complexes of the Highlands where anorthosites, charnockites and mangerites comprise a common field association. Amphibolites vary from mappable sheets that are hundreds of meters thick to thin (<1 m) layers within the host gneisses. Gabbros and diorites vary from circular to oval-shaped bodies, generally <2 km across, that may be infolded with the host rocks. Pervasive shear in Lowland granitic rocks (Hyde School Gneiss) that resulted in major sheath folds, as proposed by Tewksbury, extends into the mafic bodies whose margins show strong gneissic textures and grain size reduction, but the cores are less deformed. The Balmat gabbro varies inwardly and systematically from monzonitic to gabbroic composition in decreasing Si, Na, K, Rb, Zr and Ba, and in increasing Ca, Mg, Fe, Ti, P, Sr, Cr, V and Ni content. Y/Nb ratios remain constant at 3-4. Among explanations of assimilation and metasomatism, the authors tentatively prefer an hypothesis of exclusion of alkali material during crystallization of mafic magma. Calc alkali and low potassium tholeiites are indicated in plots of the Balmat and other mafic bodies on Ti/100-Zr-Yx3 and Ti-Zr discrimination diagrams, although there is much scatter of data. Within-plate basalts are lacking, and ocean floor basalts are indicated for some amphibolites.

  18. Hydrologic data for Mountain Creek, Trinity River basin, Texas, 1976

    USGS Publications Warehouse

    Buckner, H.D.

    1978-01-01

    The total drainage area of Mountain Creek, Texas, is 304 sq mi. The stream-gaging stations on Mountain Creek near Cedar Hill and Walnut Creek near Mansfield provide hydrologic data to define runoff characteristics from small drainage basins. They also serve as index stations for inflow into the reservoir and provide operational data for the reservoir. In addition, the station Walnut Creek near Mansfield is equipped with a recording rain gage. The stage station near Duncanville provides data pertinent to operation of the gates in the Mountain Creek Lake Dam. The reservoir-content station at the dam provides records of reservoir state and contents. The stream-gaging station Mountain Creek at Grand Prairie provides records of outflow from Mountain Creek Lake and the basin. Basin outflow for the 1976 water year was 78,660 acre-feet which is only 1,140 acre-feet above the 16-year (1960-76) average of 77,520 acre-feet. Storage in Mountain Creek Lake showed a net gain of 760 acre-feet during the water year. Rainfall over the study area for the 1976 water year was about 32 inches, which is about 2 inches below the long-term mean rainfall (1960-75) for the area. (Woodard-USGS)

  19. Water quality of Fremont Lake and New Fork Lakes, western Wyoming: A progress report

    SciTech Connect

    Peterson, D.A.; Averett, R.C.; Mora, K.L.

    1987-01-01

    Fremont Lake and New Fork Lakes in the New Fork River drainage of western Wyoming were selected for a comprehensive study of hydrologic processes affecting mountain lakes in the Rocky Mountains. Information is needed about lakes in this area to assess their response to existing and planned development. The concerns include regional issues such as acid precipitation from gas-sweetening plants, coal-fired power plants, and smelters, as well as local issues, such as shoreline development and raising outlet control structures. Onsite measurements indicated strong thermal stratification in the lakes during the summer. Isothermal conditions occurred during December 1983 and May 1984. Mean phytoplankton concentrations were less than 5,000 cells/ml, and chlorophyll a concentrations were weakly correlated with phytoplankton concentrations. Zooplankton concentrations were small, less than 6 organisms/L. The numbers of benthic invertebrates/unit area in Fremont Lake were extremely small. The lake waters and inflow and outflow streams were chemically dilute solutions. Mean dissolved-solids concentrations were 13 mg/L in Fremont Lake and 24 mg/L in New Fork Lakes. Calcium and bicarbonate were the predominant ions. Concentrations of phosphorus and nitrogen usually were less than detection limits. Trace-metals concentrations in the lakes were similar to those in precipitation and generally were small. Dissolved organic-carbon concentrations were about 1 mg/L. Concentrations of fulvic and humic acids were relatively large in the inlet of Fremont Lake during the spring. Pine Creek has deposited 800 metric tons of sediment, on an annual average, to the delta of Fremont Lake. Most sediment is deposited during spring runoff. 32 refs., 33 figs., 9 tabs.

  20. Water quality of Fremont Lake and New Fork Lakes, western Wyoming; a progress report

    USGS Publications Warehouse

    Peterson, D.A.; Averett, R.C.; Mora, K.L.

    1987-01-01

    Fremont Lake and New Fork Lakes in the New Fork River drainage of western Wyoming were selected for a comprehensive study of hydrologic processes affecting mountain lakes in the Rocky Mountains. Information is needed about lakes in this area to assess their response to existing and planned development. The concerns include regional issues such as acid precipitation from gas-sweetening plants, coal-fired powerplants, and smelters, as well as local issues, such as shoreline development and raising outlet control structures. Onsite measurements indicated strong thermal stratification in the lakes during the summer. Isothermal conditions occurred during December 1983 and May 1984. Mean phytoplankton concentrations were less than 5,000 cells/ml, and chlorophyll a concentrations were weakly correlated with phytoplankton concentrations. Zooplankton concentrations were small, less than 6 organisms/L. The numbers of benthic invertebrates/unit area in Fremont Lake were extremely small. The lake waters and inflow and outflow streams were chemically dilute solutions. Mean dissolved-solids concentrations were 13 mg/L in Fremont Lake and 24 mg/L in New Fork Lakes. Calcium and bicarbonate were the predominant ions. Concentrations of phosphorus and nitrogen usually were less than detection limits. Trace-metals concentrations in the lakes were similar to those in precipitation and generally were small. Dissolved organic-carbon concentrations were about 1 mg/L. Concentrations of fulvic and humic acids were relatively large in the inlet of Fremont Lake during the spring. Pine Creek has deposited 800 metric tons of sediment, on an annual average, to the delta of Fremont Lake. Most sediment is deposited during spring runoff. (USGS)

  1. Bryophyte dispersal inferred from colonization of an introduced substratum on Whiteface Mountain, New York.

    PubMed

    Miller, Norton G; McDaniel, Stuart F

    2004-08-01

    A long-standing debate in bryophyte biogeography concerns the frequency of long-distance spore dispersal. The diversity of bryophytes on mortared rock walls along the Veterans Memorial Highway on Whiteface Mountain, New York, USA, was studied to document the recruitment of species over the 65 years since the highway was constructed. The highway is situated in the Adirondack Mountains, a relatively unpopulated region with a largely acidic flora. The introduction of mortar has increased the bryophyte diversity by 50% above that of native lithic substrata on the mountain. The composition of the native and mortar floras differed greatly, suggesting that the walls were not colonized by locally abundant ruderal species. Many of the species sampled on the walls are typically found only in lower elevation forested sites, distant (∼5 km or more) from the highway, and not on anthropogenic calcium carbonate. These results suggest that a bryophyte community consisting of common and uncommon species assembled from distant sites at the rate of at least one species per year in the last 65 years. These data provide the ecological context for experimental and phylogeographic studies and suggest that some bryophytes may be capable of routine dispersal over distances of at least 5 km.

  2. Grand Canyon, Lake Powell, and Lake Mead

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A snowfall in the American West provides contrast to the landscape's muted earth tones and indicates changes in topography and elevation across (clockwise from top left) Nevada, Utah, Colorado, New Mexico, Arizona, and California. In Utah, the southern ranges of the Wasatch Mountains are covered in snow, and the Colorado River etches a dark ribbon across the red rock of the Colorado Plateau. In the center of the image is the reservoir created by the Glen Canyon Dam. To the east are the gray-colored slopes of Navaho Mountain, and to the southeast, dusted with snow is the region called Black Mesa. Southwest of Glen Canyon, the Colorado enters the Grand Canyon, which cuts westward through Arizona. At a deep bend in the river, the higher elevations of the Keibab Plateau have held onto snow. At the end of the Grand Canyon lies another large reservoir, Lake Mead, which is formed by the Hoover Dam. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  3. Developing recreational harvest regulations for an unexploited lake trout population

    USGS Publications Warehouse

    Lenker, Melissa A; Weidel, Brian C.; Jensen, Olaf P.; Solomon, Christopher T.

    2016-01-01

    Developing fishing regulations for previously unexploited populations presents numerous challenges, many of which stem from a scarcity of baseline information about abundance, population productivity, and expected angling pressure. We used simulation models to test the effect of six management strategies (catch and release; trophy, minimum, and maximum length limits; and protected and exploited slot length limits) on an unexploited population of Lake Trout Salvelinus namaycush in Follensby Pond, a 393-ha lake located in New York State’s Adirondack Park. We combined field and literature data and mark–recapture abundance estimates to parameterize an age-structured population model and used the model to assess the effects of each management strategy on abundance, catch per unit effort (CPUE), and harvest over a range of angler effort (0–2,000 angler-days/year). Lake Trout density (3.5 fish/ha for fish ≥ age 13, the estimated age at maturity) was similar to densities observed in other unexploited systems, but growth rate was relatively slow. Maximum harvest occurred at levels of effort ≤ 1,000 angler-days/year in all the scenarios considered. Regulations that permitted harvest of large postmaturation fish, such as New York’s standard Lake Trout minimum size limit or a trophy size limit, resulted in low harvest and high angler CPUE. Regulations that permitted harvest of small and sometimes immature fish, such as a protected slot or maximum size limit, allowed high harvest but resulted in low angler CPUE and produced rapid declines in harvest with increases in effort beyond the effort consistent with maximum yield. Management agencies can use these results to match regulations to management goals and to assess the risks of different management options for unexploited Lake Trout populations and other fish species with similar life history traits.

  4. Identifying Common Patterns in Diverse Systems: Effects of Exurban Development on Birds of the Adirondack Park and the Greater Yellowstone Ecosystem, USA

    NASA Astrophysics Data System (ADS)

    Glennon, Michale J.; Kretser, Heidi E.; Hilty, Jodi A.

    2015-02-01

    We examined the impacts of exurban development on bird communities in Essex County, New York and Madison County, Montana by comparing differences in abundance of songbirds between subdivisions and control sites in both regions. We hypothesized that impacts to bird communities would be greater in the relatively homogeneous, closed canopy Adirondack forest of northern New York State than they would be in the more naturally heterogeneous grasslands interspersed with trees and shrubs of the Greater Yellowstone Ecosystem. We examined birds in five functional groups expected to be responsive to exurban development, and determined relative abundance within subdivisions and control sites across these two distinct regions. We found little support for our hypothesis. For birds in the area-sensitive, low nesting, and Neotropical migrant functional groups, relative abundance was lower in subdivisions in the Adirondacks and in Madison County, while relative abundance of edge specialists was greater in subdivisions in both regions. The direction and magnitude of change in the avian communities between subdivisions and controls was similar in both regions for all guilds except microhabitat specialists. These similarities across diverse ecosystems suggest that the ecological context of the encompassing region may be less important than other elements in shaping avian communities in exurban systems. This finding suggests that humans and their specific behaviors and activities in exurban areas may be underappreciated but potentially important drivers of change in these regions.

  5. Identifying common patterns in diverse systems: effects of exurban development on birds of the Adirondack Park and the Greater Yellowstone Ecosystem, USA.

    PubMed

    Glennon, Michale J; Kretser, Heidi E; Hilty, Jodi A

    2015-02-01

    We examined the impacts of exurban development on bird communities in Essex County, New York and Madison County, Montana by comparing differences in abundance of songbirds between subdivisions and control sites in both regions. We hypothesized that impacts to bird communities would be greater in the relatively homogeneous, closed canopy Adirondack forest of northern New York State than they would be in the more naturally heterogeneous grasslands interspersed with trees and shrubs of the Greater Yellowstone Ecosystem. We examined birds in five functional groups expected to be responsive to exurban development, and determined relative abundance within subdivisions and control sites across these two distinct regions. We found little support for our hypothesis. For birds in the area-sensitive, low nesting, and Neotropical migrant functional groups, relative abundance was lower in subdivisions in the Adirondacks and in Madison County, while relative abundance of edge specialists was greater in subdivisions in both regions. The direction and magnitude of change in the avian communities between subdivisions and controls was similar in both regions for all guilds except microhabitat specialists. These similarities across diverse ecosystems suggest that the ecological context of the encompassing region may be less important than other elements in shaping avian communities in exurban systems. This finding suggests that humans and their specific behaviors and activities in exurban areas may be underappreciated but potentially important drivers of change in these regions.

  6. 76 FR 29264 - Minor Boundary Revision at Rocky Mountain National Park

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-20

    ... National Park Service Minor Boundary Revision at Rocky Mountain National Park AGENCY: National Park Service....S.C. 4601-9(c)(1), the boundary of Rocky Mountain National Park is modified to include an additional... National Park and northeast of Grand Lake. The boundary revision is depicted on Map No. 121/105,475...

  7. Field Evaluation of Deet and a Piperidine Repellent Against Aedes communis (Diptera: Culicidae) and Simulium venustum (Diptera: Simuliidae) in the Adirondack Mountains of New York

    DTIC Science & Technology

    2000-11-01

    confidence interval on percent repellency at 6 h ranged from 90.1 to 98.9% for AI3-37220 versus 64.3 to 82.2% for deet, and at 8 h ranged 76.1 to 88.5% for AI3-37220 versus 47.8 to 64.0% for deet. Similarly, the confidence interval ...at 6 h by AI3-37220 ranged from 86.3 to 99.5% and did not overlap with the confidence ... interval provided by deet along (51.2 to 78.8%). There was no evidence of synergistic repellency from a combination of the two compounds; i.e., protection from combined compounds was no better than either

  8. Effects of flow releases on macroinvertebrate assemblages in the Indian and Hudson Rivers in the Adirondack Mountains of Northern New York

    USGS Publications Warehouse

    Baldigo, Barry P.; Smith, A.J.

    2011-01-01

    The effects of flow releases (daily during spring and four times weekly during summer) from a small impoundment on macroinvertebrate assemblages in the lower Indian River and upper Hudson River of northern New York were assessed during the summers of 2005 and 2006. Community indices, feeding guilds, dominant species and Bray—Curtis similarities at three sites on the Indian River, below a regulated impoundment, were compared with those at four control sites on the Cedar River, below a run-of-the-river impoundment of comparable size. The same indices at four less-likely affected sites on the Hudson River, below the mouth of the Indian River, were compared with those at an upstream control site on the Hudson River. Results show that the function and apparent health of macroinvertebrate communities were generally unaffected by atypical flow regimes and/or altered water quality at study reaches downstream from both dams in the Indian, Cedar and Hudson Rivers. The lentic nature of releases from both impoundments, however, produced significant changes in the structure of assemblages at Indian and Cedar River sites immediately downstream from both dams, moderate effects at two Indian River sites 2.4 and 4.0 km downstream from its dam, little or no effect at three Cedar River sites 7.2-34.2 km downstream from its dam, and no effect at any Hudson River site. Bray—Curtis similarities indicate that assemblages did not differ significantly among sites within similar impact categories. The paucity of scrapers at all Indian River sites, and the predominance of filter-feeding Simulium gouldingi and Pisidium compressum immediately below Abanakee dam, show that only minor differences in dominant species and trophic structure of macroinvertebrate communities occurred at affected sites in the Indian River compared to the Cedar River. Thus, flow releases had only a small, localized effect on macroinvertebrate communities in the Indian River.

  9. Contaminant Monitoring Strategy for Henrys Lake, Idaho

    SciTech Connect

    John S. Irving; R. P. Breckenridge

    1992-12-01

    Henrys Lake, located in southeastern Idaho, is a large, shallow lake (6,600 acres, {approx} 17.1 feet maximum depth) located at 6,472 feet elevation in Fremont Co., Idaho at the headwaters of the Henrys Fork of the Snake River. The upper watershed is comprised of high mountains of the Targhee National Forest and the lakeshore is surrounded by extensive flats and wetlands, which are mostly privately owned. The lake has been dammed since 1922, and the upper 12 feet of the lake waters are allocated for downriver use. Henrys Lake is a naturally productive lake supporting a nationally recognized ''Blue Ribbon'' trout fishery. There is concern that increasing housing development and cattle grazing may accelerate eutrophication and result in winter and early spring fish kills. There has not been a recent thorough assessment of lake water quality. However, the Department of Environmental Quality (DEQ) is currently conducting a study of water quality on Henrys Lake and tributary streams. Septic systems and lawn runoff from housing developments on the north, west, and southwest shores could potentially contribute to the nutrient enrichment of the lake. Many houses are on steep hillsides where runoff from lawns, driveways, etc. drain into wetland flats along the lake or directly into the lake. In addition, seepage from septic systems (drainfields) drain directly into the wetlands enter groundwater areas that seep into the lake. Cattle grazing along the lake margin, riparian areas, and uplands is likely accelerating erosion and nutrient enrichment. Also, cattle grazing along riparian areas likely adds to nutrient enrichment of the lake through subsurface flow and direct runoff. Stream bank and lakeshore erosion may also accelerate eutrophication by increasing the sedimentation of the lake. Approximately nine streams feed the lake (see map), but flows are often severely reduced or completely eliminated due to irrigation diversion. In addition, subsurface flows can occur as a

  10. Blanket of Snow Covers Salt Lake City

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On December 23, 2001, less than two months before the start of the 2002 Winter Olympics, snow blankets Salt Lake City and the surrounding area. The Great Salt Lake, on the left hand side of the image above, often contributes to the region's snowfall through the 'lake-effect.' As cold air passes over a large body of water it both warms and absorbs moisture. The warm air then rises (like a hot air balloon) and cools again. As it cools, the water vapor condenses out, resulting in snowfall. Just to the east (right) of the Great Salt Lake the mountains of the Wasatch Range lift air from the lake even higher, enhancing the lake-effect, resulting in an average snowfall of 64 inches a year in Salt Lake City and 140 inches in Park City, which is located at the foot of the Wasatch Front. For more information about the lake-effect, read Lake-Effect Snowfalls. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  11. Mountain rescue stretchers: usability trial.

    PubMed

    Hignett, Sue; Willmott, Joseph Wayne; Clemes, Stacy

    2009-01-01

    In the UK mountain rescues are carried out by highly trained volunteers in all weather conditions and at any time of the day/night. They interface with other services when they hand over the casualty to either land or air ambulances. The design of the stretcher is important to the safety of both the volunteers and casualties. This paper reports a usability trial to evaluate the features of mountain rescue stretchers and identify characteristics for future design. Two mountain rescue teams in the English Lake District participated in a five week field experiment. Data were collected using postural analysis with Rapid Entire Body Analysis, Body Part Discomfort Surveys, Rated Perceived Exertion and focus groups to compare the performance of four stretchers: Split Thomas, Ferno Titan, MacInnes mark 6 and MacInnes mark 7. None of the stretchers had an overall advantage, with benefits for some features counterbalanced by disadvantages resulting from others. All the stretchers produced shoulder discomfort with the Split Thomas and MacInnes 6 lowering the postural risks through the use of skids/wheel in the carrying phase. The key design features for future MR stretchers include: reduced unloaded weight (e.g. light weight materials and mesh platforms); undercarriage system to reduce the carrying load; adjustable handles at the front and back positions; flexible carrying system with an optional harness attachment; ease of assembly in adverse environmental conditions; large carrying capacity. It is suggested that military emergency evacuation should be considered in addition to mountain rescue tasks to identify a larger commercial market for development.

  12. Geography of Alaska Lake Districts: Identification, Description, and Analysis of Lake-Rich Regions of a Diverse and Dynamic State

    USGS Publications Warehouse

    Arp, Christopher D.; Jones, Benjamin M.

    2009-01-01

    Lakes are abundant landforms and important ecosystems in Alaska, but are unevenly distributed on the landscape with expansive lake-poor regions and several lake-rich regions. Such lake-rich areas are termed lake districts and have landscape characteristics that can be considered distinctive in similar respects to mountain ranges. In this report, we explore the nature of lake-rich areas by quantitatively identifying Alaska's lake districts, describing and comparing their physical characteristics, and analyzing how Alaska lake districts are naturally organized and correspond to climatic and geophysical characteristics, as well as studied and managed by people. We use a digital dataset (National Hydrography Dataset) of lakes greater than 1 hectare, which includes 409,040 individual lakes and represents 3.3 percent of the land-surface area of Alaska. The selection criteria we used to identify lake districts were (1) a lake area (termed limnetic ratio, in percent) greater than the mean for the State, and (2) a lake density (number of lakes per unit area) greater than the mean for the State using a pixel size scaled to the area of interest and number of lakes in the census. Pixels meeting these criteria were grouped and delineated and all groups greater than 1,000 square kilometers were identified as Alaska's lake districts. These lake districts were described according to lake size-frequency metrics, elevation distributions, geology, climate, and ecoregions to better understand their similarities and differences. We also looked at where lake research and relevant ecological monitoring has occurred in Alaska relative to lake districts and how lake district lands and waters are currently managed. We identified and delineated 20 lake districts in Alaska representing 16 percent of the State, but including 65 percent of lakes and 75 percent of lake area. The largest lake districts identified are the Yukon-Kuskokwim Delta, Arctic Coastal Plain, and Iliamna lake districts with

  13. Lake Constance

    Atmospheric Science Data Center

    2013-04-17

    ... Swiss shores of Lake Constance at the town of Rorschach. Eutrophication, or the process of nutrient enrichment, is rapidly accelerated ... of the value of Lake Constance, efforts to mitigate eutrophication were initiated in the 1970's. MISR was built and is managed ...

  14. Climatic and limnologic setting of Bear Lake, Utah and Idaho

    USGS Publications Warehouse

    Dean, W.E.; Wurtsbaugh, W.A.; Lamarra, V.A.

    2009-01-01

    Bear Lake is a large alkaline lake on a high plateau on the Utah-Idaho border. The Bear River was partly diverted into the lake in the early twentieth century so that Bear Lake could serve as a reservoir to supply water for hydropower and irrigation downstream, which continues today. The northern Rocky Mountain region is within the belt of the strongest of the westerly winds that transport moisture during the winter and spring over coastal mountain ranges and into the Great Basin and Rocky Mountains. As a result of this dominant winter precipitation pattern, most of the water entering the lake is from snowmelt, but with net evaporation. The dominant solutes in the lake water are Ca 2+, Mg2+, and HCO32-, derived from Paleozoic carbonate rocks in the Bear River Range west of the lake. The lake is saturated with calcite, aragonite, and dolomite at all depths, and produces vast amounts of carbonate minerals. The chemistry of the lake has changed considerably over the past 100 years as a result of the diversion of Bear River. The net effect of the diversion was to dilute the lake water, especially the Mg2+ concentration. Bear Lake is oligotrophic and coprecipitation of phosphate with CaCO3 helps to keep productivity low. However, algal growth is colimited by nitrogen availability. Phytoplankton densities are low, with a mean summer chlorophyll a concentration of 0.4 mg L-1. Phytoplankton are dominated by diatoms, but they have not been studied extensively (but see Moser and Kimball, this volume). Zooplankton densities usually are low (<10 L-1) and highly seasonal, dominated by calanoid copepods and cladocera. Benthic invertebrate densities are extremely low; chironomid larvae are dominant at depths <30 m, and are partially replaced with ostracodes and oligochaetes in deeper water. The ostracode species in water depths >10 m are all endemic. Bear Lake has 13 species of fi sh, four of which are endemic. Copyright ?? 2009 The Geological Society of America.

  15. Potentially dangerous glacial lakes in Kyrgyzstan - Research overview of 2004-2015

    NASA Astrophysics Data System (ADS)

    Jansky, Bohumir; Yerokhin, Sergey; Sobr, Miroslav; Engel, Zbynek; Cerny, Michal; Falatkova, Kristyna; Kocum, Jan; Benes, Vojtech

    2016-04-01

    Global warming causes intensive melting and retreat of glaciers in most of high mountains all over the world. This process is also evident in the mountain regions of central Tien Shan. Glacier melt water affects changes in hydrological regime of water streams and causes overfilling of high mountain lake basins. The dams of many lakes are very unstable and can burst open. To determine the degree of such risk, it is necessary to analyse the genesis of lakes, to characterize the morphology of the lake basins and to know the particularities of their hydrological regime. According to the latest inventory within territory of Kyrgyzstan, a total of 1328 lakes have been identified as potentially dangerous, 12 lakes are considered as currently dangerous, other 25 feature high potential hazard. Since 1952 more than 70 disastrous cases of lake outburst have been registered. The hazardous alpine lakes are studied in Kyrgyzstan systematically since 1966. Since 2004, Czech-Kyrgyz research team has been operating in Kyrgyzstan in the field of dangerous glacial lakes. Projects were focused primarily on high-mountain glacial lakes risk assessment, propositions of risk mitigation measures, establishment of permanent research station near one of the studied glacier complexes, preparation of risk analysis for selected endangered valleys, evaluation of climatic and hydrological data and glacier development within observed regions. The most significant portion of data and information has been gathered during field work, complemented by satellite image analysis and surveillance flights over the monitored sites.

  16. Eruptive history of Mammoth Mountain and its mafic periphery, California

    USGS Publications Warehouse

    Hildreth, Wes; Fierstein, Judy

    2016-07-13

    Many geographic names that appear in this report are informal despite having been in local use for decades. Most appear on maps distributed by the Town of Mammoth Lakes or the Mammoth Mountain Ski Area and can be found here on map figures 2–5, on several photo figures, and on the geologic map.

  17. Rocky Mountain spotted fever

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000654.htm Rocky Mountain spotted fever To use the sharing features on this page, please enable JavaScript. Rocky Mountain spotted fever is a disease caused by a type of ...

  18. Lesson 2: Sacred Mountains.

    ERIC Educational Resources Information Center

    Byers, Alton; Gilligan, Nancy; Golston, Syd; Linville, Rex

    1999-01-01

    Presents a lesson in which the students are divided into four Mountain Study Teams in order to examine a sacred mountain. Explains that the students in each group assume a particular role, such as an historian or scientist. Provides a profile on the four mountains and a definition of the seven student roles. (CMK)

  19. Ecological status assessment of Skalenski Lakes (Bulgaria)

    PubMed Central

    Teneva, Ivanka; Gecheva, Gana; Cheshmedjiev, Svetoslav; Stoyanov, Plamen; Mladenov, Rumen; Belkinova, Detelina

    2014-01-01

    Over the past decade new ecological indices based on phytoplankton and macrophytes were developed as part of the tools for assessment of the ecological status of water bodies. This study demonstrates the applicability of two of them (Assemblage index /Q/ and Algae Group Index /AGI/) for evaluation of water bodies from a lake type L4 as well as their comparability. Assessment of the ecological status of two lake ecosystems was performed in order to ensure successful protection, enhancement and management of lowland and semi-mountain lakes in Bulgaria. Data on the aquatic flora from Golyamo Skalensko Lake and Malko Skalensko Lake over a period of two years were used to assess their ecological status. In addition, the toxic potential of the established dominant cyanoprokaryotic species was also evaluated. Phytoplankton- and macrophyte-based metrics resulted in complementary evaluation of temporary and long-term environmental conditions. Despite the hydraulic connection and proximity between the two lakes, Golyamo Skalensko Lake and Malko Skalensko Lake appear as completely different ecosystems, according to the phytoplankton structure (species composition, number of species, abundance, seasonal succession), macrophytes and ecological status. PMID:26019492

  20. Ecological status assessment of Skalenski Lakes (Bulgaria).

    PubMed

    Teneva, Ivanka; Gecheva, Gana; Cheshmedjiev, Svetoslav; Stoyanov, Plamen; Mladenov, Rumen; Belkinova, Detelina

    2014-01-02

    Over the past decade new ecological indices based on phytoplankton and macrophytes were developed as part of the tools for assessment of the ecological status of water bodies. This study demonstrates the applicability of two of them (Assemblage index /Q/ and Algae Group Index /AGI/) for evaluation of water bodies from a lake type L4 as well as their comparability. Assessment of the ecological status of two lake ecosystems was performed in order to ensure successful protection, enhancement and management of lowland and semi-mountain lakes in Bulgaria. Data on the aquatic flora from Golyamo Skalensko Lake and Malko Skalensko Lake over a period of two years were used to assess their ecological status. In addition, the toxic potential of the established dominant cyanoprokaryotic species was also evaluated. Phytoplankton- and macrophyte-based metrics resulted in complementary evaluation of temporary and long-term environmental conditions. Despite the hydraulic connection and proximity between the two lakes, Golyamo Skalensko Lake and Malko Skalensko Lake appear as completely different ecosystems, according to the phytoplankton structure (species composition, number of species, abundance, seasonal succession), macrophytes and ecological status.

  1. Relative Contributions of Phosphorus in High Elevation Sierra Nevada Lakes

    NASA Astrophysics Data System (ADS)

    Jensen, L. K.; McIntyre, B. M.; Lyons, R. A.

    2015-12-01

    High elevation lakes of the Sierra Nevada mountain range show signs of eutrophication due to increased phosphorus loading. Phosphorus is a major contributing factor to freshwater lake eutrophication when in excess. Three previously researched sources of phosphorus to high-elevation montane lakes include atmospheric deposition, internal loading from sediments, and excretions from non-native stocked fish. The goal of this research was to isolate the estimated phosphorus contributions from residential shoreline developments and stocked non-native fish. A steady-state phosphorus loading rate model was created to quantify relative phosphorus loading into two lakes in the Eastern Sierra Nevada: Convict and Silver Lake. A conglomerate control lake was created from Eastern Brook Lake in the Eastern Sierra Nevada, Pear Lake in the Southern Sierra Nevada, and Snowflake Lake in Canada. Both Convict and Silver Lakes contain stocked non-native trout species and Silver Lake also has ~25 vacation homes on its eastern shore. Seasonal steady-state total phosphorus concentrations were determined using EPA Method 365.2. Loading rate constants were calculated using loading rates from literature and corresponding concentrations. It was determined that as much as 42% of phosphorous to Silver Lake came from shoreline housing developments, and 24% came from stocked fish depending on the season. Previous studies showed much lower contributions from non-native fish.

  2. Pleistocene lake level changes in Western Mongolia

    NASA Astrophysics Data System (ADS)

    Borodavko, P. S.

    2009-04-01

    Global cooling in the Early Pleistocene caused extensive continental glaciation in the northern hemisphere including the arid areas of Central Asia. The reduction of temperatures (particularly summer temperatures) reduced evaporation and strengthened the importance of precipitation. The simultaneity of "lakes periods" (pluvials) and stages of glaciation is established experience confirmed by investigations in the west of North America and Russia. In the Mongolian Great Lakes Depression new evidence for similar conditions is found. The Great Lakes Depression is one of the largest in Central Asia, and is divided into 2 main Lakes basins: Hyargas Lake Basin and Uvs Lake Basin. The basin is 600-650 km in length with a width of 200-250 km in the north and 60-100 km in the south. Total catchment area is about 186600 km2. The elevation of the basin floor is from 1700 m a.s.l. to 760 m a.s.l., decreasing to the north and south-east. The depression extends south-north and is bounded by mountains: Tannu-Ola to the north, Hangai to the east; Gobi Altai to the south and Mongolian Altay to the west. The maximum elevation of the mountains is 4000 m a.s.l. There are some mountains with an elevation between 2000 and 3000 m a.s.l in the lake catchment. These mountains are not glaciated today. The geological record [1] suggests the Great Lakes Depression already existed in the Mesozoic, but assumed its modern form only during the Pliocene-Quaternary when tectonic movements caused the uplift of the surrounding mountains. A phase of tectonic stability occurred during the Late Quaternary. The depression is filled by Quaternary fluvial, aeolian and lacustrine deposits (e.g. sand, pebbles). The Neogene deposits are represented by coloured clay, marl, sand and sandstone [1]. Hyargas Lake is the end base level of erosion of the lake group consisting of the Hara-Us Nur, Dorgon, Hara Nur and Airag lakes. Hyargas is one of the largest lakes in Mongolia, with a water surface of 1,407 km2. The

  3. Epidemiology of acute mountain sickness on Jade Mountain, Taiwan: an annual prospective observational study.

    PubMed

    Wang, Shih-Hao; Chen, Yu-Cheng; Kao, Wei-Fong; Lin, Yu-Jr; Chen, Jih-Chang; Chiu, Te-Fa; Hsu, Tai-Yi; Chen, Hang-Cheng; Liu, Shih-Wei

    2010-01-01

    Acute mountain sickness (AMS) is a pathophysiological symptom complex that occurs in high altitude areas. The AMS prevalence is reportedly 28% on Jade Mountain, the highest mountain (3952 m) in Taiwan. We conducted this study owing to the lack of annual epidemiological data on AMS in Taiwan. Between April 2007 and March 2008, 1066 questionnaires were completed by trekkers visiting Paiyun Lodge on Jade Mountain. Information in the questionnaire included demographic data, mountaineering experience, AMS history, and trekking schedule. Weather data were obtained from the Central Weather Bureau of Taiwan. The Lake Louise AMS score was used to record symptoms and diagnose AMS. The chi-square test or the Student t test was used to evaluate associations between variables and AMS. In our study, the AMS prevalence was 36%. It increased significantly at different rates at different locations on the Jade Mountain trail and varied significantly in different months. Rainy weather tended to slightly increase the incidence of AMS. A lower incidence of AMS was correlated with hig-altitude trekking experience or preexposure (p < 0.05), whereas a higher incidence of AMS was correlated with a prior history of AMS (p < 0.05). The trekkers with AMS were significantly younger, ascended faster from their residence to the entrance or to Paiyun Lodge, and ascended slower from the entrance to the Paiyun Lodge (p < 0.05), but the differences lacked clinical significance. No differences in the incidence of AMS based on blood type, gender, or obesity were observed. The most common symptom among all trekkers was headache, followed by difficulty sleeping, fatigue or weakness, gastrointestinal (GI) symptoms, and dizziness or lightheadedness. In conclusion, the AMS prevalence on Jade Mountain was 36%, varied by month, and correlated with trekking experience, preexposure, and a prior history of AMS. The overall presentation of AMS was similar to that on other major world mountains.

  4. White Lake AOC

    EPA Pesticide Factsheets

    White Lake is in Muskegon County along the eastern shore of Lake Michigan. It was named an Area of Concern on the Great Lakes under the Great Lakes Water Quality Agreement of 1987 and delisted in 2014.

  5. I. An /sup 18/O//sup 16/O investigation of the Lake City caldera, San Juan Mountains, Colorado. II. /sup 18/O//sup 16/O relationships in tertiary ash-flow tuffs from complex caldera structures in central Nevada and the San Juan Mountains, Colorado

    SciTech Connect

    Larson, P.B.

    1984-01-01

    /sup 18/O//sup 16/O analyses were made on 355 samples in and around the 11 by 14 km Lake City calders, which formed 23 m.y. ago in response to the eruption of the rhyolitic Sunshine Peak Tuff. All of the major lithologies and hydrothermal alteration facies were analyzed, and a detailed delta/sup 18/O map was made of the caldera and its surroundings. The delta/sup 18/O values within the Lake City caldera are controlled by elevation, proximity to permeable zones, and proxmity to the resurgent intrusive rocks. delta/sup 18/O values decrease systematically with stratigraphic depth within the caldera. Mineralogic alteration facies within the caldera show complementary patterns. These data show that the resurgent intrusion was the heat engine that drove the Lake City hydrothermal system. Alteration in and near the intrusion occurred at high temperatures and intermediate water/rock ratios. Away from the resurgent intrusion, water-rock interaction in the permeable zones occurred at lower temperatures and high water/rock ratios. The regional eastward tilting has raised low-/sup 18/O rocks in the western part of the caldera to higher elevations than stratigraphically equivalent rocks in the eastern part of the caldera. Mineralogical alteration patterns are also similarly displaced.

  6. Highly Polar Organic Compounds in Summer Cloud Water from Whiteface Mountain, NY

    NASA Astrophysics Data System (ADS)

    Sagona, J. A.; Dukett, J. E.; Mazurek, M.

    2010-12-01

    Highly polar organic compounds (HPOC) containing multiple oxygen atoms are of interest due to the aerosol direct and indirect effects and uncertainty they may contribute to climate forcing. Atmospheric HPOC exist as particulate or dissolved chemical species depending on relative humidity. HPOC solid mixtures are thought to scatter and absorb light due to particle size and color (white to yellow). Understanding the chemical composition of HPOC in cloud water (CW) is important for modeling and predicting the direct and indirect influences of this organic aerosol component on the climate system. In this initial study we present a detailed molecular examination of 10 CW samples. CW samples were collected in September 2009 using an automated CW collector at Whiteface Mountain (elevation 1483 m) in the Adirondack Mountains in upstate NY. We performed QA/QC experiments for the CW samples and analyzed the HPOC mixtures by ultratrace gas chromatography/mass spectrometry. Diacids such as oxalic acid and succinic acid were major components of the CW HPOC with concentrations on the order of 15 ng/mL. Substituted diacids, monoacids, and sugars also were present. We discuss the possible sources of these compounds in light of back-trajectory analysis.

  7. An inventory of glacial lakes in the Austrian Alps

    NASA Astrophysics Data System (ADS)

    Buckel, Johannes; Otto, Jan-Christoph; Keuschnig, Markus; Götz, Joachim

    2016-04-01

    The formation of lakes is one of the consequences of glacier retreat due to climate change in mountain areas. Numerous lakes have formed in the past few decades in many mountain regions around the globe. Some of these lakes came into focus due to catastrophic hazard events especially in the Himalayas and the Andes. Glacial lake development and lifetime is controlled by the complex interplay of glacier dynamics, geomorphological process activity and geological boundary conditions. Besides the hazard potential new lakes in formerly glaciated areas will significantly contribute to a new landscape setting and to changing geomorphologic, hydrologic and ecologic conditions at higher alpine altitudes. We present an inventory of high alpine lakes in the Austrian Alps located above an altitude of 1700 m asl. Most of these lakes are assumed to be of glacial origin, but other causes for development, like mass movements are considered as well. The inventory is a central part of the project FUTURELAKES that aims at modelling the potential development of glacial lakes in Austria (we refer to the presentation by Helfricht et al. during the conference for more details on the modelling part). Lake inventory data will serve as one basis for model validation since modelling is performed on different time steps using glacier inventory data. The purpose of the lake inventory is to get new insights into boundary conditions for lake formation and evolution by analysing existing lake settings. Based on these information the project seeks to establish a model of lake sedimentation after glacier retreat in order to assess the potential lifetime of the new lakes in Austria. Lakes with a minimum size of 1000 m² were mapped using multiple aerial imagery sources. The dataset contains information on location, geometry, dam type, and status of sedimentation for each lake. Additionally, various geologic, geomorphic and morphometric parameters describe the lake catchments. Lake data is related to

  8. Measurement of ridge-spreading movements (Sackungen) at Bald Eagle Mountain, Lake County, Colorado, II : continuation of the 1975-1989 measurements using a Global Positioning System in 1997 and 1999

    USGS Publications Warehouse

    Varnes, David J.; Coe, J.A.; Godt, J.W.; Savage, W.Z.; Savage, J.E.

    2000-01-01

    Measurements of ridge-spreading movements at Bald Eagle Mountain in north-central Colorado were reported in USGS Open-File Report 90-543 for the years 1975-1989. Measurements were renewed in 1997 and 1999 using the Global Positioning System (GPS). Movements are generally away from a ridge-top graben and appear to be concentrated along 3 or 4 trenches with uphill facing scarps that are parallel with slope contours. A point just below the lowest trench has moved the most? a total of 8.3 cm horizontally and slightly downward from 1977 to 1999 relative to an assumed stable point on the periphery of the graben. Movements from 1997 to 1999 are less than 1 cm or within the error of measurement.

  9. Geologic reconnaissance of the Hot Springs Mountains, Churchill County, Nevada

    USGS Publications Warehouse

    Voegtly, Nickolas E.

    1981-01-01

    A geologic reconnaissance of the Hot Springs Mountains and adjacent areas, which include parts of the Brady-Hazen and the Stillwater-Soda Lake Known Geothermal Resource Areas, during June-December 1975, resulted in a reinterpretation of the nature and location of some Basin and Range faults. In addition, the late Cenozoic stratigraphy has been modified, chiefly on the basis of radiometric dates of volcanic rocks by U.S. Geological Survey personnel and others. The Hot Springs Mountains are in the western part of the Basin and Range province, which is characterized by east-west crustal extension and associated normal faulting. In the surrounding Trinity, West Humboldt, Stillwater, and Desert Mountains, Cenozoic rocks overlie ' basement ' rocks of the Paleozoic and Mesozoic age. A similar relation is inferred in the Hot Springs Mountains. Folding and faulting have taken place from the late Tertiary to the present. (USGS)

  10. Lake Powell

    NASA Technical Reports Server (NTRS)

    2007-01-01

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

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

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

  11. Lake acidification

    SciTech Connect

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

    1987-06-01

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

  12. 9. DETAIL OF DIVERSION STRUCTURE WEST OF DERBY LAKE (SECTION ...

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

    9. DETAIL OF DIVERSION STRUCTURE WEST OF DERBY LAKE (SECTION 2) SHOWING DIVERSION GATE TO LAKE LADORA. - Highline Canal, Sand Creek Lateral, Beginning at intersection of Peoria Street & Highline Canal in Arapahoe County (City of Aurora), Sand Creek lateral Extends 15 miles Northerly through Araphoe County, City & County of Denver, & Adams County to its end point, approximately 1/4 mile Southest of intersectioin of D Street & Ninth Avenue in Adams County (Rocky Mountain Arsenal, Commerce City Vicinity), Commerce City, Adams County, CO

  13. Geologic map database of the El Mirage Lake area, San Bernardino and Los Angeles Counties, California

    USGS Publications Warehouse

    Miller, David M.; Bedford, David R.

    2000-01-01

    This geologic map database for the El Mirage Lake area describes geologic materials for the dry lake, parts of the adjacent Shadow Mountains and Adobe Mountain, and much of the piedmont extending south from the lake upward toward the San Gabriel Mountains. This area lies within the western Mojave Desert of San Bernardino and Los Angeles Counties, southeastern California. The area is traversed by a few paved highways that service the community of El Mirage, and by numerous dirt roads that lead to outlying properties. An off-highway vehicle area established by the Bureau of Land Management encompasses the dry lake and much of the land north and east of the lake. The physiography of the area consists of the dry lake, flanking mud and sand flats and alluvial piedmonts, and a few sharp craggy mountains. This digital geologic map database, intended for use at 1:24,000-scale, describes and portrays the rock units and surficial deposits of the El Mirage Lake area. The map database was prepared to aid in a water-resource assessment of the area by providing surface geologic information with which deepergroundwater-bearing units may be understood. The area mapped covers the Shadow Mountains SE and parts of the Shadow Mountains, Adobe Mountain, and El Mirage 7.5-minute quadrangles. The map includes detailed geology of surface and bedrock deposits, which represent a significant update from previous bedrock geologic maps by Dibblee (1960) and Troxel and Gunderson (1970), and the surficial geologic map of Ponti and Burke (1980); it incorporates a fringe of the detailed bedrock mapping in the Shadow Mountains by Martin (1992). The map data were assembled as a digital database using ARC/INFO to enable wider applications than traditional paper-product geologic maps and to provide for efficient meshing with other digital data bases prepared by the U.S. Geological Survey's Southern California Areal Mapping Project.

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

    NASA Astrophysics Data System (ADS)

    Pan, Hai

    1999-08-01

    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

  15. Lake Bonneville

    USGS Publications Warehouse

    Gilbert, Grove Karl

    1890-01-01

    This volume is a contribution to the later physical history of the Great Basin. As a geographic province the Great Basin is characterized by a dry climate, changes of drainage, volcanic eruption, and crustal displacement. Lake Bonneville, the special theme of the volume, was a phenomenon of climate and drainage, but its complete history includes an account of contemporaneous eruption and displacement.

  16. Lake Buchannan, Great Dividing Range, Queensland, Australia

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Lake Buchannan, a small but blue and prominent in the center of the view, lies in the Great Dividing of Queensland, Australia (22.0S, 146.0E). The mountain range in this case is a low plateau of no more than 2,000 to 3,000 ft altitude. The interior is dry, mostly in pasture but the coastal zone in contrast, is wet tropical country where bananas and sugarcane are grown.

  17. ALPINE LAKES WILDERNESS STUDY AREA, WASHINGTON.

    USGS Publications Warehouse

    Gualtieri, J.L.; Thurber, H.K.

    1984-01-01

    The Alpine Lakes Wilderness study area, located in the central part of the Cascade Mountains of Washington was examined for its mineral-resource potential. On the basis of that study the area was found to contain deposits of copper, other base metals, and gold and silver. Probable or substantiated mineral-resource potential exists for these commodities in the southwest-central, northwest, and southeast-central parts of the area. The geologic terrane precludes the occurrence of fossil fuel resources.

  18. Deglaciation and postglacial timberline in the San Juan Mountains, Colorado

    USGS Publications Warehouse

    Carrara, P.E.; Mode, W.N.; Rubin, M.; Robinson, S.W.

    1984-01-01

    Lake Emma, which no longer exists because of a mining accident, was a tarn in a south-facing cirque near the headwaters of the Animas River in the San Juan Mountains of southwestern Colorado. During the Pinedale glaciation, this area was covered by a large transection glacier centered over the Lake Emma region. Three radiocarbon dates on basal organic sediment from Lake Emma indicate that by ca. 15,000 yr B.P. this glacier, one of the largest in the southern Rocky Mountains, no longer existed. Twenty-two radiocarbon dates on Picea and Abies krummholz fragments in the Lake Emma deposits indicate that from ca. 9600 to 7800 yr B.P., from 6700 to 5600 yr B.P., and at 3100 yr B.P. the krummholz limit was at least 70 m higher than present. These data, in conjunction with Picea:Pinus pollen ratios from both the Lake Emma site and the Hurricane Basin site of J. T. Andrews, P. E. Carrara, F. B. King, and R. Struckenrath (1975, Quaternary Research 5, 173-197) suggest than from ca. 9600 to 3000 yr B.P. timberline in the San Juan Mountains was higher than present. Cooling apparently began ca. 3000 yr B.P. as indicated by decreases in both the percentage of Picea pollen and Picea:Pinus pollen ratios at the Hurricane Basin site (Andrews et al., 1975). Cooling is also suggested by the lack of Picea or Abies fragments younger than 3000 yr B.P. at either the Lake Emma or the Hurricane Basin site. ?? 1984.

  19. Establishing eutrophication assessment standards for four lake regions, China.

    PubMed

    Huo, Shouliang; Ma, Chunzi; Xi, Beidou; Su, Jing; Zan, Fengyu; Ji, Danfeng; He, Zhuoshi

    2013-10-01

    The trophic status assessment of lakes in different lake regions may provide important and fundamental information for lake trophic state classification and eutrophication control. In this study, a region-specific lake eutrophication assessment standard was established through a frequency distribution method based on chlorophyll-a concentration. The assessment standards under the oligotrophic state for lakes in the Eastern plain, Yungui Plateau, Northeast Plain and Mountain Mongolia-Xinjiang regions are total phosphorus of 0.068, 0.005, 0.011, 0.005 mg/L; total nitrogen of 1.00, 0.16, 0.37, 0.60 mg/L; Secchi depth of 0.60, 8.00, 1.55, 3.00 m; and COD(Mn) of 2.24, 1.00, 5.11, 4.00 mg/L, respectively. Moreover, a region-specific comprehensive trophic level index was developed to provide an understandable assessment method for the public. The results indicated that the frequency distribution analysis based on chlorophyll-a combined with trophic level index provided a useful metric for the assessment of the lake trophic status. In addition, the difference of eutrophication assessment standards in different lake regions was analyzed, which suggested that the sensitivities of algae to nutrients and the assessment standard of trophic status possessed significant regional differences for the four lake ecoregions. Lake eutrophication assessment standards would contribute to maximizing the effectiveness of future management strategies, to control and minimize lake eutrophication problems.

  20. Persistent toxic substances in remote lake and coastal sediments from Svalbard, Norwegian Arctic: levels, sources and fluxes.

    PubMed

    Jiao, Liping; Zheng, Gene J; Minh, Tu Binh; Richardson, Bruce; Chen, Liqi; Zhang, Yuanhui; Yeung, Leo W; Lam, James C W; Yang, Xulin; Lam, Paul K S; Wong, Ming H

    2009-04-01

    Surface sediments from remote lakes and coastal areas from Ny-Alesund, Svalbard, Norwegian Arctic were analyzed for polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). Relatively high levels of PAHs were encountered from several lakes from Ny-Alesund, which were within the range of levels reported for European high mountain lakes and some urban/industrialized areas in the world, pointing to the role of remote Arctic lakes as potential reservoir of semi-volatile organic compounds. Specific patterns of PBDEs were observed, showing higher concentrations of lower brominated compounds such as BDE-7, 17 and 28. Estimated surface sediment fluxes of PAHs in Ny-Alesund remote lakes were similar to those observed for some European high mountain lakes. The current PAH levels in sediments from three lakes exceeded Canadian sediment quality guidelines, suggesting the presence of possible risks for aquatic organisms and the need for further studies.

  1. Pesticides in mountain yellow-legged frogs (Rana muscosa) from the Sierra Nevada Mountains of California, USA

    USGS Publications Warehouse

    Fellers, G.M.; McConnell, L.L.; Pratt, D.; Datta, S.

    2004-01-01

    In 1997, pesticide concentrations were measured in mountain yellow-legged frogs (Rana muscosa) from two areas in the Sierra Nevada Mountains of California, USA. One area (Sixty Lakes Basin, Kings Canyon National Park) had large, apparently healthy populations of frogs. A second area (Tablelands, Sequoia National Park) once had large populations, but the species had been extirpated from this area by the early 1980s. The Tablelands is exposed directly to prevailing winds from agricultural regions to the west. When an experimental reintroduction of R. muscosa in 1994 to 1995 was deemed unsuccessful in 1997, the last 20 (reintroduced) frogs that could be found were collected from the Tablelands, and pesticide concentrations in both frog tissue and the water were measured at both the Tablelands and at reference sites at Sixty Lakes. In frog tissues, dichlorodiphenyldichloroethylene (DDE) concentration was one to two orders of magnitude higher than the other organochlorines (46 ?? 20 ng/g wet wt at Tablelands and 17 ?? 8 Sixty Lakes). Both ??-chlordane and trans-nonachlor were found in significantly greater concentrations in Tablelands frog tissues compared with Sixty Lakes. Organophosphate insecticides, chlorpyrifos, and diazinon were observed primarily in surface water with higher concentrations at the Tablelands sites. No contaminants were significantly higher in our Sixty Lakes samples.

  2. Hydrogeologic setting, ground-water flow, and ground-water quality at the Lake Wheeler Road research station, 2001-03 : North Carolina Piedmont and Mountains Resource Evaluation Program

    USGS Publications Warehouse

    Chapman, Melinda J.; Bolich, Richard E.; Huffman, Brad A.

    2005-01-01

    Results of a 2-year field study of the regolith-fractured bedrock ground-water system at the Lake Wheeler Road research station in Wake County, North Carolina, indicate both disconnection and interaction among components of the ground-water system. The three components of the ground-water system include (1) shallow, porous regolith; (2) a transition zone, including partially weathered rock, having both secondary (fractures) and primary porosity; and (3) deeper, fractured bedrock that has little, if any, primary porosity and is dominated by secondary fractures. The research station includes 15 wells (including a well transect from topographic high to low settings) completed in the three major components of the ground-water-flow system and a surface-water gaging station on an unnamed tributary. The Lake Wheeler Road research station is considered representative of a felsic gneiss hydrogeologic unit having steeply dipping foliation and a relatively thick overlying regolith. Bedrock foliation generally strikes N. 10? E. to N. 30? E. and N. 20? W. to N. 40? W. to a depth of about 400 feet and dips between 70? and 80? SE. and NE., respectively. From 400 to 600 feet, the foliation generally strikes N. 70? E. to N. 80? E., dipping 70? to 80? SE. Depth to bedrock locally ranges from about 67 to 77 feet below land surface. Fractures in the bedrock generally occur in two primary sets: low dip angle, stress relief fractures that cross cut foliation, and steeply dipping fractures parallel to foliation. Findings of this study generally support the conceptual models of ground-water flow from high to low topographic settings developed for the Piedmont and Blue Ridge Provinces in previous investigations, but are considered a refinement of the generalized conceptual model based on a detailed local-scale investigation. Ground water flows toward a surface-water boundary, and hydraulic gradients generally are downward in recharge areas and upward in discharge areas; however, local

  3. Glacier change and glacial lake outburst flood risk in the Bolivian Andes

    NASA Astrophysics Data System (ADS)

    Cook, Simon J.; Kougkoulos, Ioannis; Edwards, Laura A.; Dortch, Jason; Hoffmann, Dirk

    2016-10-01

    Glaciers of the Bolivian Andes represent an important water resource for Andean cities and mountain communities, yet relatively little work has assessed changes in their extent over recent decades. In many mountain regions, glacier recession has been accompanied by the development of proglacial lakes, which can pose a glacial lake outburst flood (GLOF) hazard. However, no studies have assessed the development of such lakes in Bolivia despite recent GLOF incidents here. Our mapping from satellite imagery reveals an overall areal shrinkage of 228.1 ± 22.8 km2 (43.1 %) across the Bolivian Cordillera Oriental between 1986 and 2014. Shrinkage was greatest in the Tres Cruces region (47.3 %), followed by the Cordillera Apolobamba (43.1 %) and Cordillera Real (41.9 %). A growing number of proglacial lakes have developed as glaciers have receded, in accordance with trends in most other deglaciating mountain ranges, although the number of ice-contact lakes has decreased. The reasons for this are unclear, but the pattern of lake change has varied significantly throughout the study period, suggesting that monitoring of future lake development is required as ice continues to recede. Ultimately, we use our 2014 database of proglacial lakes to assess GLOF risk across the Bolivian Andes. We identify 25 lakes that pose a potential GLOF threat to downstream communities and infrastructure. We suggest that further studies of potential GLOF impacts are urgently required.

  4. Formation of Fe/mg Smectite Under Acidic Conditions from Synthetic Adirondack Basaltic Glass: an Analog to Fe/mg Smectite Formation on Mars

    NASA Technical Reports Server (NTRS)

    Sutter, B.; Peretyazhko, T.; Morris, R. V.; Ming, D. W.

    2014-01-01

    Smectite has been detected as layered material hundreds of meters thick, in intracrater depositional fans, in plains sediments, and deposits at depth on Mars. If early Mars hosted a dense CO2 atmosphere, then extensive carbonate should have formed in the neutral/alkaline conditions expected for smectite formation. However, large carbonate deposits on Mars have not been discovered. Instead of neutral to moderately alkaline conditions, early Mars may have experienced mildly acidic conditions that allowed for Fe/Mg smectite formation but prevented widespread carbonate formation. The objective of this work is to demonstrate that Fe(II)/Mg saponite and nontronite can form in mildly acidic solutions (e.g., pH 4). Synthetic basaltic glass (< 53 microns) of Adirondack rock class composition was exposed to pH 4 (acetic acid buffer) and N2 purged (anoxic) solutions amended with 0 and 10 mM Mg or Fe(II). Basaltic glass in these solutions was heated to 200 C in batch reactors for 1, 7, and 14 days. X-ray diffraction analysis of reacted materials detected the presence of phyllosilicates as indicated by a approx. 15.03-15.23Angstroms (001) peak. Smectite was confirmed as the phyllosilicate after treatments with glycerol and KCl and heating to 550 C. Trioctahedral saponite was confirmed by the presence of a 4.58 to 4.63 Angstroms (02l) and 1.54Angstroms (060) peaks. Saponite concentration was highest, as indicated by XRD peak intensity, in the 10 mM Mg treatment followed by the 0 mM and then 10 mM Fe(II) treatments. This order of sapontite concentration suggests that Fe(II) additions may have a role in slowing the kinetics of saponite formation relative to the other treatments. Nontronite synthesis was attempted by exposing Adirondack basaltic glass to pH 4 oxic solutions (without N2 purge) at 200 C for 14 days. X-ray diffraction analysis indicated that mixtures of trioctahedral (saponite) and dioctahedral (nontronite) may have formed in these experiments based on the 02l and 060

  5. Formation of Fe/Mg Smectite under acidic conditions from synthetic Adirondack Basaltic Glass: An Analog to Fe/Mg Smectite Formation on Mars.

    NASA Astrophysics Data System (ADS)

    Sutter, B.; Peretyazhko, T.; Morris, R. V.; Ming, D. W.

    2014-12-01

    Smectite has been detected as layered material hundreds of meters thick, in intracrater depositional fans, in plains sediments, and deposits at depth on Mars. If early Mars hosted a dense CO2 atmosphere, then extensive carbonate should have formed in the neutral/alkaline conditions expected for smectite formation. However, large carbonate deposits on Mars have not been discovered. Instead of neutral to moderately alkaline conditions, early Mars may have experienced mildly acidic conditions that allowed for Fe/Mg smectite formation but prevented widespread carbonate formation. The objective of this work is to demonstrate that Fe(II)/Mg-saponite and nontronite can form in mildly acidic solutions (e.g., pH 4). Synthetic basaltic glass (< 53 μm) of Adirondack rock class composition was exposed to pH 4 (acetic acid buffer) and N2 purged (anoxic) solutions amended with 0 and 10 mM Mg or Fe(II). Basaltic glass in these solutions was heated to 200ºC in batch reactors for 1, 7, and 14 days. X-ray diffraction analysis of reacted materials detected the presence of phyllosilicates as indicated by a ~15.03-15.23Ǻ (001) peak. Smectite was confirmed as the phyllosilicate after treatments with glycerol and KCl and heating to 550°C. Trioctahedral saponite was confirmed by the presence of a 4.58 to 4.63 Ǻ (02l) and 1.54Ǻ (060) peaks. Saponite concentration was highest, as indicated by XRD peak intensity, in the 10 mM Mg treatment followed by the 0 mM and then 10 mM Fe(II) treatments. This order of sapontite concentration suggests that Fe(II) additions may have a role in slowing the kinetics of saponite formation relative to the other treatments. Nontronite synthesis was attempted by exposing Adirondack basaltic glass to pH 4 oxic solutions (without N2 purge) at 200ºC for 14 days. X-ray diffraction analysis indicated that mixtures of trioctahedral (saponite) and dioctahedral (nontronite) may have formed in these experiments based on the 02l and 060 peaks. Mössbauer analysis

  6. Macroinvertebrates as indicators of fish absence in naturally fishless lakes

    USGS Publications Warehouse

    Schilling, Emily Gaenzle; Loftin, C.S.; Huryn, Alexander D.

    2009-01-01

    1. Little is known about native communities in naturally fishless lakes in eastern North America, a region where fish stocking has led to a decline in these habitats. 2. Our study objectives were to: (i) characterise and compare macroinvertebrate communities in fishless lakes found in two biophysical regions of Maine (U.S.A.): kettle lakes in the eastern lowlands and foothills and headwater lakes in the central and western mountains; (ii) identify unique attributes of fishless lake macroinvertebrate communities compared to lakes with fish and (iii) develop a method to efficiently identify fishless lakes when thorough fish surveys are not possible. 3. We quantified macroinvertebrate community structure in the two physiographic fishless lake types (n = 8 kettle lakes; n = 8 headwater lakes) with submerged light traps and sweep nets. We also compared fishless lake macroinvertebrate communities to those in fish-containing lakes (n = 18) of similar size, location and maximum depth. We used non-metric multidimensional scaling to assess differences in community structure and t-tests for taxon-specific comparisons between lakes. 4. Few differences in macroinvertebrate communities between the two physiographic fishless lake types were apparent. Fishless and fish-containing lakes had numerous differences in macroinvertebrate community structure, abundance, taxonomic composition and species richness. Fish presence or absence was a stronger determinant of community structure in our study than differences in physical conditions relating to lake origin and physiography. 5. Communities in fishless lakes were more speciose and abundant than in fish-containing lakes, especially taxa that are large, active and free-swimming. Families differing in abundance and taxonomic composition included Notonectidae, Corixidae, Gyrinidae, Dytiscidae, Aeshnidae, Libellulidae and Chaoboridae. 6. We identified six taxa unique to fishless lakes that are robust indicators of fish absence: Graphoderus

  7. Schlumberger soundings near Medicine Lake, California

    USGS Publications Warehouse

    Zohdy, A.A.R.; Bisdorf, R.J.

    1990-01-01

    The use of direct current resistivity soundings to explore the geothermal potential of the Medicine Lake area in northern California proved to be challenging because of high contact resistances and winding roads. Deep Schlumberger soundings were made by expanding current electrode spacings along the winding roads. Corrected sounding data were interpreted using an automatic interpretation method. Forty-two maps of interpreted resistivity were calculated for depths extending from 20 to 1000 m. Computer animation of these 42 maps revealed that: 1) certain subtle anomalies migrate laterallly with depth and can be traced to their origin, 2) an extensive volume of low-resistivity material underlies the survey area, and 3) the three areas (east of Bullseye Lake, southwest of Glass Mountain, and northwest of Medicine Lake) may be favorable geothermal targets. Six interpreted resistivity maps and three cross-sections illustrate the above findings. -from Authors

  8. Salt Lake City, Utah

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The 2002 Winter Olympics are hosted by Salt Lake City at several venues within the city, in nearby cities, and within the adjacent Wasatch Mountains. This simulated natural color image presents a late spring view of north central Utah that includes all of the Olympic sites. The image extends from Ogden in the north, to Provo in the south; and includes the snow-capped Wasatch Mountains and the eastern part of the Great Salt Lake.

    This image was acquired on May 28, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18,1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The Terra mission is part of NASA's Earth Science Enterprise, a long-term research and technology program designed to examine Earth's land, oceans, atmosphere, ice and life as a total integrated system.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution

  9. GLOF, Glacial Lake Mapping an ESA DUE Innovator 2 Project

    NASA Astrophysics Data System (ADS)

    Wiesmann, Andreas; Strozzi, Tazio; Kaab, Andreas

    2010-12-01

    Glacier lake outbursts have repeatedly been the cause of major fatal events and damage in, for instance, the Himalayas, Central Asia, Andes, Caucasus, and the European Alps. The related hazards may even currently increase due to climate change as glaciers worldwide retreat and leave under certain circumstances glacier lakes behind. As a particularly far-reaching glacier- related hazard, glacier lake outburst floods may have devastating impact on populated areas that are located far downstream of the source area. Glacial lakes are often located in inaccessible areas, or can only be accessed with a substantial effort and cost to investigate their condition. While e.g. in Switzerland a network is setup to monitor glacier changes and help prevent glacial hazards, large and inaccessible areas e.g. in the Pamir and Himalayan mountains cannot be easily monitored from ground and air. Spaceborne remote sensing data are therefore a valuable and important information source to collect information on glacial lakes in these areas.

  10. 30. Otter Lake Dam. View shows rustic stone facade of ...

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

    30. Otter Lake Dam. View shows rustic stone facade of the dam. The stepped face of the dam gives the illusion of a natural cascade. Facing southeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  11. 260. View of the Pinnacle Lake Overlook. Example of location ...

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

    260. View of the Pinnacle Lake Overlook. Example of location where designers placed an overlook on the outside of a curve instead of leaving the remnants of a rock cut visible. View to the south. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  12. Chemistry of selected high-elevation lakes in seven national parks in the western United States

    USGS Publications Warehouse

    Clow, David W.; Striegl, Robert G.; Nanus, Leora; Mast, M. Alisa; Campbell, Donald H.; Krabbenhoft, David P.

    2002-01-01

    A chemical survey of 69 high-altitude lakes in seven national parks in the western United States was conducted during the fallof 1999; the lakes were previously sampled during the fall of 1985, as part of the Western Lake Survey. Lakes in parks in the Sierra/southern Cascades (Lassen Volcanic, Yosemite, Sequoia/Kings Canyon National Parks) and in the southern RockyMountains (Rocky Mountain National Park) were very dilute; medianspecific conductance ranged from 4.4 to 12.2 μS cm-1 andmedian alkalinity concentrations ranged from 32.2 to 72.9 μeqL-1. Specific conductances and alkalinity concentrations were substantially higher in lakes in the central and northernRocky Mountains parks (Grand Teton, Yellowstone, and GlacierNational Parks), probably due to the prevalence of more reactivebedrock types. Regional patterns in lake concentrations of NO3 and SO4 were similar to regional patterns in NO3 and SO4 concentrations in precipitation, suggestingthat the lakes are showing a response to atmospheric deposition.Concentrations of NO3 were particularly high in Rocky Mountain National Park, where some ecosystems appear to be undergoing nitrogen saturation.

  13. Geothermal Potential of Marine Corps Mountain Warfare Training Center at Pickel Meadow, California.

    DTIC Science & Technology

    1983-05-01

    AD-A131 460 GEOTHERMAL POTENTIAL OF MARINE CORPS MOUNTAIN WARFARE TRAININO CENTER AT PICKEL MEADOW CALIFORNIANU NAVALWEAPONS CENTER CHINA LAKE CA K...ATOAL’ 8u*Au OF STANOAO - 196 3 -A ONWC Technical Memorandum 4898 GEOTHERMAL POTENTIAL OF MARINE CORPS MOUNTAIN WARFARE TRAINING CENTER AT PICKEL...MEADOW, CALIFORNIA by .Kathy Danti J. A. Whelan Allan M. Katzenstein Geothermal Utilization Division Public Works Department May 1983 Approved for public

  14. Winter and Summer Views of the Salt Lake Region

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Magnificent views of the region surrounding Salt Lake City, Utah are captured in these winter and summer images from the Multi-angle Imaging SpectroRadiometer's vertical-viewing (nadir) camera. Salt Lake City, situated near the southeastern shore of the Great Salt Lake, is host to the 2002 Winter Olympic Games, which open Friday, February 8. Venues for five of the scheduled events are at city (indoor) locations, and five in mountain (outdoor) facilities. All ten can be found within the area contained in these images. Some of the outdoor events take place at Ogden, situated north of Salt Lake City and at Park City, located to the east. Salt Lake City is surrounded by mountains including the Wasatch Range to the east, and the temperature difference between the Great Salt Lake and the overlying atmosphere enhances the moisture content of winter storms. These factors, in combination with natural cloud seeding by salt crystals from the lake, are believed to result in greater snowfall in neighboring areas compared to more distant locales. In addition to the obvious difference in snow cover between the winter and summer views, water color changes in parts of the Great Salt Lake are apparent in these images. The distinctly different coloration between the northern and southern arms of the Great Salt Lake is the result of a rock-filled causeway built in 1953 to support a permanent railroad. The causeway has resulted in decreased circulation between the two arms and higher salinity on the northern side. The southern part of the lake includes the large Antelope Island, and at full resolution a bridge connecting it to the mainland can be discerned. These images are natural color views acquired on February 8, 2001 and June 16, 2001, respectively. Each image represents an area of about 220 kilometers x 285 kilometers. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team.

  15. Geohydrology and evapotranspiration at Franklin Lake playa, Inyo County, California

    SciTech Connect

    Czarnecki, J.B.

    1997-12-31

    Franklin Lake playa is one of the principal discharge areas of the Furnace Creek Ranch-Alkali Flat ground-water-flow system in southern Nevada and adjacent California. Yucca Mountain, Nevada, located within this flow system, is being evaluated by the US Department of Energy to determine its suitability as a potential site for a high-level nuclear-waste repository. To assist the U.S. Department of Energy with its evaluation of the Yucca Mountain site, the US Geological Survey developed a parameter-estimation model of the Furnace Creek Ranch-Alkali Flat ground-water-flow system. Results from sensitivity analyses made using the parameter-estimation model indicated that simulated rates of evapotranspiration at Franklin Lake playa had the largest effect on the calculation of transmissivity values at Yucca Mountain of all the model-boundary conditions and, therefore, that evapotranspiration required careful definition.

  16. Geohydrology and evapotranspiration at Franklin Lake Playa, Inyo County, California

    SciTech Connect

    1990-12-01

    Franklin Lake playa is one of the principal discharge areas of the Furnace Creek Ranch-Alkali Flat ground-water-flow system in southern Nevada and adjacent California. Yucca Mountain, Nevada, located within this flow system, is being evaluated by the US Department of Energy to determine its suitability as a potential site for a high-level nuclear-waste repository. To assist the US Department of Energy with its evaluation of the Yucca Mountain site, the US Geological Survey developed a parameter-estimation model of the Furnace Creek Ranch-Alkali Flat ground-water-flow system. Results from sensitivity analyses made using the parameter-estimation model indicated that simulated rates of evapotranspiration at Franklin Lake playa had the largest effect on the calculation of transmissivity values at Yucca Mountain of all the model-boundary conditions and, therefore, that evapotranspiration required careful definition. 72 refs., 59 figs., 26 tab.

  17. Mountain regions in peril

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    The United Nations has declared 2002 the International Year of Mountains (IYM) to bring attention to a number of threats that affect ecosystems and human populations in mountainous and highland regions around the world.“More than half of humanity—3 billion people—relies on mountains for safe, fresh water, water to grow food, to produce electricity to sustain industries and, most important, water to drink,“ said Jacques Diouf, director-general of the U.N. Food and Agriculture Organization, the primary IYM sponsor. “Yet, mountain glaciers, the source of water for many of the world's river systems and people, are melting at unprecedented rates.”

  18. Acute mountain sickness

    MedlinePlus

    High altitude cerebral edema; Altitude anoxia; Altitude sickness; Mountain sickness; High altitude pulmonary edema ... If you have fluid in your lungs (pulmonary edema), treatment may include: Oxygen A high blood pressure ...

  19. Response of lake chemistry to atmospheric deposition and climate in selected Class I wilderness areas in the western United States, 1993-2009

    USGS Publications Warehouse

    Mast, M. Alisa

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Forest Service, Air Resource Management, conducted a study to evaluate long-term trends in lake-water chemistry for 64 high-elevation lakes in selected Class I wilderness areas in Colorado, Idaho, Utah, and Wyoming during 1993 to 2009. Understanding how and why lake chemistry is changing in mountain areas is essential for effectively managing and protecting high-elevation aquatic ecosystems. Trends in emissions, atmospheric deposition, and climate variables (air temperature and precipitation amount) were evaluated over a similar period of record. A main objective of the study was to determine if changes in atmospheric deposition of contaminants in the Rocky Mountain region have resulted in measurable changes in the chemistry of high-elevation lakes. A second objective was to investigate linkages between lake chemistry and air temperature and precipitation to improve understanding of the sensitivity of mountain lakes to climate variability.

  20. The state and their implication of Himalayan glacial lake changes from satellite observations

    NASA Astrophysics Data System (ADS)

    Nie, Y.; Sheng, Y.; Liu, Q.; Liu, L.; Liu, S.; Zhang, Y.; Song, C.

    2015-12-01

    Glacial lake outburst floods (GLOFs)generally result in catastrophic damages and fatalities. The Himalayas, the world's highest mountains hosting large number of glaciers, have frequently suffered from GLOFs events in the past decades. Climatic warming-induced melting and retreating glaciers make glacial lakes expand obviously and urge the potential risk of GLOFs in Himalayas. However, our knowledge on the state of glacial lakes in the entire Himalayas is still limited. This study conducts a systematically satellite-based inventory to firstly reveal the evolution complex, regional difference and causes of Himalayan glacial lake changes in the whole Himalayas. Hundreds of Landsat images and Google Earth high resolution imagery were employed to extract the extents of glacial lakes at four epochs (circa1990, circa 2000, circa 2005 and circa 2010). Object-oriented mapping method was used to automatically map the lakes. In association with published glacier data (e.g., China Glacier Inventory, Randolph and GLIMS Glacier data), visual inspections and iterative checks for individual lake guarantee the accuracy of our results. This study demonstrates the spatial and topographic distributions, differences, heterogeneity of glacial lake changes and their causes. Our results show that Himalayan glacial lakes present a rapidly expanding state in general. Both disappeared lakes and new-formed lakes were observed, however, pre-existing glacial lakes contributed most to the total areal expansion. Himalayan glacial lakes appeared a clear altitudinal difference between north side and south side of main range. Evolutions of glacial lakes between eastern, western and central Himalaya were different, and the most rapidly expanding areas need to be more concerned. Climatic and geomorphic controls result in the heterogeneity of glacial lake changes. This study will help assess the potential risk of GLOFs and promote the public awareness of glacial disasters in high mountain areas.

  1. YUCCA MOUNTAIN SITE DESCRIPTION

    SciTech Connect

    A.M. Simmons

    2004-04-16

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel.

  2. Mountain Rivers Revisited

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2011-12-01

    Published in 2000, the original Mountain Rivers was written to provide a concise summary of the scientific understanding of the distinct subset of rivers that gave the book its name. Spurred by developments in the field in the past decade, the book's author, Ellen Wohl, produced Mountain Rivers Revisited, an updated edition aimed at graduate students and professional researchers. In this interview, Eos talks to Wohl about steep channels, climate change, and opportunities for future research.

  3. Hurricane Mountain Formation melange: history of Cambro-Ordovician accretion of the Boundary Mountains terrane within the northern Appalachian orthotectonic zone

    SciTech Connect

    Boone, G.M.; Boudette, E.L.

    1985-01-01

    The Hurricane Mountain Formation (HMF) melange and associated ophiolitic and volcanogenic formations of Cambrian and lowermost Ordovician age bound the SE margin of the Precambrian Y (Helikian) Chain Lakes Massif in western Maine. HMF melange matrix, though weakly metamorphosed, contains a wide variety of exotic greenschist to amphibolite facies blocks as components of its polymictic assemblage, but blocks of high-grade cratonal rocks such as those of Chain Lakes or Grenville affinity are lacking. Formations of melange exposed in structural culminations of Cambrian and Ordovician rocks NE of the HMF in Maine and in the Fournier Group in New Brunswick are lithologically similar and probably tectonically correlative with the HMF; taken together, they may delineate a common pre-Middle Ordovician tectonic boundary. The authors infer that the Hurricane Mountain and St. Daniel melange belts define the SE and NW margins of the Boundary Mountains accreted terrane (BMT), which may consist of cratonal basement of Chain Lakes affinity extending from eastern Gaspe (deBroucker and St. Julien, 1985) to north-central New Hampshire. The Laurentian continental margin, underlain by Grenville basement, underplated the NW margin of this terrane, marked by the SDF suture zone, in late Cambrian to early Ordovician time, while terranes marked by Cambrian to Tremadocian (.) lithologies dissimilar to the Boundary Mountains terrane were accreted to its outboard margin penecontemporaneously. The docking of the Boundary Mountains terrane and the initiation of its peripheral melanges are equated to the Penobscottian disturbance.

  4. Application of ERTS-1 imagery and underflight photography in the detection and monitoring of forest insect infestations in the Sierra Nevada Mountains of California

    NASA Technical Reports Server (NTRS)

    Hall, R. C.

    1973-01-01

    The analysis of ERTS-1 imagery of areas in the Sierra Nevada Mountains of California is discussed. The data is used to detect two types of insect infestational and to determine the extent of timber resources. Addition applications are the mapping of stream courses, mountain meadows, lakes, rock outcrops, and grazing land. The ERTS-1 data and underflight photography are used for this purpose.

  5. Anaglyph, Salt Lake City, Utah

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The 2002 Winter Olympics are hosted by Salt Lake City at several venues within the city, in nearby cities, and within the adjacent Wasatch Mountains. This anaglyph image provides a stereoscopic map view of north central Utah that includes all of these Olympic sites. In the south, next to Utah Lake, Provo hosts the ice hockey competition. In the north, northeast of the Great Salt Lake, Ogden hosts curling and the nearby Snowbasin ski area hosts the downhill events. In between, southeast of the Great Salt Lake, Salt Lake City hosts the Olympic Village and the various skating events. Further east, across the Wasatch Mountains, the Park City ski resort hosts the bobsled, ski jumping, and snowboarding events. The Winter Olympics are always hosted in mountainous terrain. This view shows the dramatic landscape that makes the Salt Lake City region a world-class center for winter sports.

    The stereoscopic effect of this anaglyph was created by first draping a Landsat satellite image over a Shuttle Radar Topography Mission digital elevation model and then generating two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter.

    Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive, managed by the U.S. Geological Survey (USGS).

    Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM

  6. Geochemical evolution of Great Salt Lake, Utah, USA

    USGS Publications Warehouse

    Jones, B.F.; Naftz, D.L.; Spencer, R.J.; Oviatt, Charles G.

    2009-01-01

    The Great Salt Lake (GSL) of Utah, USA, is the largest saline lake in North America, and its brines are some of the most concentrated anywhere in the world. The lake occupies a closed basin system whose chemistry reflects solute inputs from the weathering of a diverse suite of rocks in its drainage basin. GSL is the remnant of a much larger lacustrine body, Lake Bonneville, and it has a long history of carbonate deposition. Inflow to the lake is from three major rivers that drain mountain ranges to the east and empty into the southern arm of the lake, from precipitation directly on the lake, and from minor groundwater inflow. Outflow is by evaporation. The greatest solute inputs are from calcium bicarbonate river waters mixed with sodium chloride-type springs and groundwaters. Prior to 1930 the lake concentration inversely tracked lake volume, which reflected climatic variation in the drainage, but since then salt precipitation and re-solution, primarily halite and mirabilite, have periodically modified lake-brine chemistry through density stratification and compositional differentiation. In addition, construction of a railway causeway has restricted circulation, nearly isolating the northern from the southern part of the lake, leading to halite precipitation in the north. These and other conditions have created brine differentiation, mixing, and fractional precipitation of salts as major factors in solute evolution. Pore fluids and diagenetic reactions have been identified as important sources and especially sinks for CaCO3, Mg, and K in the lake, depending on the concentration gradient and clays. ?? U.S. Geological Survey 2008.

  7. Allogenic sedimentary components of Bear Lake, Utah and Idaho

    USGS Publications Warehouse

    Rosenbaum, J.G.; Dean, W.E.; Reynolds, R.L.; Reheis, M.C.

    2009-01-01

    Bear Lake is a long-lived lake filling a tectonic depression between the Bear River Range to the west and the Bear River Plateau to the east, and straddling the border between Utah and Idaho. Mineralogy, elemental geochemistry, and magnetic properties provide information about variations in provenance of allogenic lithic material in last-glacial-age, quartz-rich sediment in Bear Lake. Grain-size data from the siliciclastic fraction of late-glacial to Holocene carbonate-rich sediments provide information about variations in lake level. For the quartz-rich lower unit, which was deposited while the Bear River fl owed into and out of the lake, four source areas are recognized on the basis of modern fluvial samples with contrasting properties that reflect differences in bedrock geology and in magnetite content from dust. One of these areas is underlain by hematite-rich Uinta Mountain Group rocks in the headwaters of the Bear River. Although Uinta Mountain Group rocks make up a small fraction of the catchment, hematite-rich material from this area is an important component of the lower unit. This material is interpreted to be glacial fl our. Variations in the input of glacial flour are interpreted as having caused quasi-cyclical variations in mineralogical and elemental concentrations, and in magnetic properties within the lower unit. The carbonate-rich younger unit was deposited under conditions similar to those of the modern lake, with the Bear River largely bypassing the lake. For two cores taken in more than 30 m of water, median grain sizes in this unit range from ???6 ??m to more than 30 ??m, with the coarsest grain sizes associated with beach or shallow-water deposits. Similar grain-size variations are observed as a function of water depth in the modern lake and provide the basis for interpreting the core grain-size data in terms of lake level. Copyright ?? 2009 The Geological Society of America.

  8. Latest Isopach Mapping of Holocene Rhyolitic Tephras at Medicine Lake Volcano, Northern California

    NASA Astrophysics Data System (ADS)

    Ramsey, D. W.; Miller, C. D.

    2011-12-01

    Medicine Lake Volcano, located in the southern Cascades ~55 km east-northeast of Mount Shasta, is a large rear-arc, shield-shaped volcano with an eruptive history spanning nearly 500,000 years. The most recent eruptions at Medicine Lake Volcano are the late Holocene explosive to effusive events at Glass Mountain (~950 yr) and Little Glass Mountain (~1000 yr), which began as sub-Plinian to Plinian eruptions of rhyolite pumice from fissure vents, and culminated in the rhyolite-dacite of Glass Mountain and the rhyolite of Little Glass Mountain. Vents for these eruptions lie along fissures located 15 km apart on opposite sides of the summit caldera of Medicine Lake Volcano. Previous mapping of these deposits by Fisher (1964) and by Heiken (1978) showed a strong northeast-southwest trend of the Little Glass Mountain tephras. Our latest isopach maps of primary tephra deposits from the Glass Mountain and Little Glass Mountain eruptions are based on more extensive fieldwork and on a different interpretation of Little Glass Mountain tephras than previous work Our work shows a strong northeast-southwest trend of the Little Glass Mountain tephras and extends the deposit further in the direction of Mount Shasta, where C. D. Miller found individual lapilli from the Little Glass Mountain eruption. This plume direction is unusual given the dominant westerly wind directions in the region. Winds blow from the northeast less than 2 percent of the time in a typical year. Our field investigations have also shown that Little Glass Mountain tephras consist of two distinct deposits: a coarse, white, pumiceous deposit erupted from Little Glass Mountain and found along the strong northeast-southwest trend; and a fine-grained, salmon-colored tephra erupted from fissure vents north of Little Glass Mountain around Crater Glass Flow and found to the north and east. Field relationships show that the salmon-colored tephra was erupted just prior to the white, pumiceous tephra, and that its fine

  9. Lake Volta, Ghana

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This true-color image of Lake Volta in Ghana was acquired March 31, 2002 by the Moderate Resolution Imaging Spectroradiometer (MODIS). Lake Volta is one of the world's largest artificially created lakes. Lake Volta is actually a reservoir formed from the damming of the Volta River, and extends 250 miles north of the Akosombo Dam. The lake covers an area of 8,482 square km. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  10. spatial and temporal distribution of nutrients in a linked stream-lake ecosystem

    NASA Astrophysics Data System (ADS)

    Kalinin, A. V.; Covino, T. P.; McGlynn, B. L.

    2011-12-01

    The movement of nutrients between streams and lakes can impact nutrient export and aquatic ecology in linked stream-lake ecosystems. Specifically, lakes can alter water chemistry and buffer downstream export of nutrients through physical, chemical, and biological processes. This study characterizes nitrogen storage and transport dynamics in a connected stream-lake ecosystem over the summer of 2008 in the Bull Trout Lake Watershed in the Sawtooth Mountains of central Idaho, USA. Water samples were collected for chemical analyses at the lake inflow, outflow, and at six sites across the lake, on hourly to bi-weekly intervals. Lake sampling sites were each sampled at six depths in order to capture all strata of the lake. Additionally, a dye-tracer (Rhodamine-WT) was co-injected with LiCl into the lake to determine water flow-paths and residence time distributions. Inflow and outflow fluxes, spatial and temporal distributions of dissolved organic nitrogen(DON) and dissolved inorganic nitrogen (DIN), as well as water residence times at different lake depths were evaluated. Over the summer of 2008, net influx of NO3 to the lake and net export of DON and NH4 from the lake was observed. While NO3 dominated the DIN fraction at the inflow, NH4 was dominant both at the lake outflow and within the lake, suggesting potential contributions of NH4 to the lake from adjacent wetland and groundwater sources. Differences in transport dynamics between NO3 and NH4, and temporal concentration dynamics both in the stream and lake support this hypothesis. NO3 concentrations were driven by snowmelt flushing and peaked with the hydrograph, subsequently declining for the rest of the summer. NH4 concentrations however remained stable and peaked three weeks after NO3 at the lake outflow, at a time when the contribution of snow melt water had declined and groundwater contribution increased proportionally. In the lake, NH4 and DON concentrations declined during peak runoff in May and June, and

  11. Distribution and prevention of dammed lakes triggered by Wenchuan earthquake

    NASA Astrophysics Data System (ADS)

    Han, Yongshun; Liu, Hongjiang; Zhu, Boqin; Han, Jun; Yang, Yingchang; Zhang, Yu

    2010-11-01

    Wenchuan earthquake induced large-scale of collapses and landslides which blocked river channels and brought about quantities of dammed lakes. The number and the scale of dammed lakes are extremely rare in the world. Besides the backwater of the dammed lakes can flood the road traffic, villages and farmland on the upstream, it can severely threaten the safety of the people's lives and properties on the downstream. Once the dammed lakes burst out, they can cause severe flood disaster. Therefore, it is urgent to monitor the dammed lakes, study their distribution and analyze their development by means of remote sensing (RS) and geography information system (GIS) after the earthquake. In this paper, 145 high-resolution images were processed and 31 severely-afflicted counties were studied through RS monitoring and field investigation. By the time of May 28,2008, 257 dammed lakes existing more than 14 days were identified and there were 34 dammed lakes with capacity of more than 100 000m3. Based on these conditions, the distribution and development of dammed lakes were discussed and the findings showed that: (a) The dammed lakes induced by Wenchuan earthquake mainly scatter in Beichuan, Wenchuan, Shifang, Mianzhu and Anxian counties, and there exist 154 dammed lakes in these regions, which is 59.92 percent of the total. (b) 95.3 percent of the dammed lakes are within 10km of three major fault zones of Longmen Mountains and the relationship between the number of dammed lakes and their distance to fault zone accords with the law of logarithmic decrement. (c) Most of dammed lakes are distributed in the upper reaches of Minjiang River, Tuojiang River, Jianjiang River and Fujiang River, etc. in rosary. (d) The distribution of dammed lakes in the study areas is dominated by seismic intensity, lithology, slope and altitude. In the next 5-10 years, collapses, landslides and debris flows in the study area will occur frequently and severely and they are likely to block river

  12. Planktonic and sedimentary bacterial diversity of Lake Sayram in summer

    PubMed Central

    Fang, Lei; Chen, Lei; Liu, Yuan; Tao, Wei; Zhang, Zhongzhe; Liu, Haiying; Tang, Yong

    2015-01-01

    Lake Sayram is an ancient cold water lake locating at a mountain basin in Xinjiang, China. The lake water is brackish, alkaline, unpolluted, and abundant in SO42− and Mg2+. The lacustrine ecosystem of Lake Sayram has been intensely investigated. However, profiles of the microbial communities in the lake remain largely unknown. In this study, taxonomic compositions of the planktonic and sedimentary bacterial communities in Lake Sayram were investigated using 16S rRNA metagenomics. The lacustrine bacterial communities were generally structured by environmental conditions, including the hydrological and physicochemical parameters. Proteobacteria was the dominating phylum. In the lake water, the genera Acinetobacter and Ilumatobacter held an absolute predominance, implying their metabolic significance. In the bottom sediment, biogeochemically significant bacteria and thermophilic or acidothermophilic extremophiles were recovered. In contrast to the planktonic bacteria, an appreciable portion of the sedimentary bacteria could not be classified into any known taxonomic unit, indicating the largely unknown bacteriosphere hiding in the bottom sediment of Lake Sayram. PMID:26242906

  13. Rapid changes in the level of Kluane Lake in Yukon Territory over the last millennium

    NASA Astrophysics Data System (ADS)

    Clague, John J.; Luckman, Brian H.; Van Dorp, Richard D.; Gilbert, Robert; Froese, Duane; Jensen, Britta J. L.; Reyes, Alberto V.

    2006-09-01

    The level of Kluane Lake, the largest lake in Yukon Territory, was lower than at present during most of the Holocene. The lake rose rapidly in the late seventeenth century to a level 12 m above present, drowning forest and stranding driftwood on a conspicuous high-stand beach, remnants of which are preserved at the south end of the lake. Kluane Lake fell back to near its present level by the end of the eighteenth century and has fluctuated within a range of about 3 m over the last 50 yr. The primary control on historic fluctuations in lake level is the discharge of Slims River, the largest source of water to the lake. We use tree ring and radiocarbon ages, stratigraphy and sub-bottom acoustic data to evaluate two explanations for the dramatic changes in the level of Kluane Lake. Our data support the hypothesis of Hugh Bostock, who suggested in 1969 that the maximum Little Ice Age advance of Kaskawulsh Glacier deposited large amounts of sediment in the Slims River valley and established the present course of Slims River into Kluane Lake. Bostock argued that these events caused the lake to rise and eventually overflow to the north. The overflowing waters incised the Duke River fan at the north end of Kluane Lake and lowered the lake to its present level. This study highlights the potentially dramatic impacts of climate change on regional hydrology during the Little Ice Age in glacierised mountains.

  14. Modeled effects of soil acidification on long-term ecological and economic outcomes for managed forests in the Adirondack region (USA).

    PubMed

    Caputo, Jesse; Beier, Colin M; Sullivan, Timothy J; Lawrence, Gregory B

    2016-09-15

    Sugar maple (Acer saccharum) is among the most ecologically and economically important tree species in North America, and its growth and regeneration is often the focus of silvicultural practices in northern hardwood forests. A key stressor for sugar maple (SM) is acid rain, which depletes base cations from poorly-buffered forest soils and has been associated with much lower SM vigor, growth, and recruitment. However, the potential interactions between forest management and soil acidification - and their implications for the sustainability of SM and its economic and cultural benefits - have not been investigated. In this study, we simulated the development of 50 extant SM stands in the western Adirondack region of NY (USA) for 100years under different soil chemical conditions and silvicultural prescriptions. We found that interactions between management prescription and soil base saturation will strongly shape the ability to maintain SM in managed forests. Below 12% base saturation, SM did not regenerate sufficiently after harvest and was replaced mainly by red maple (Acer rubrum) and American beech (Fagus grandifolia). Loss of SM on acid-impaired sites was predicted regardless of whether the shelterwood or diameter-limit prescriptions were used. On soils with sufficient base saturation, models predicted that SM will regenerate after harvest and be sustained for future rotations. We then estimated how these different post-harvest outcomes, mediated by acid impairment of forest soils, would affect the potential monetary value of ecosystem services provided by SM forests. Model simulations indicated that a management strategy focused on syrup production - although not feasible across the vast areas where acid impairment has occurred - may generate the greatest economic return. Although pollution from acid rain is declining, its long-term legacy in forest soils will shape future options for sustainable forestry and ecosystem stewardship in the northern hardwood

  15. Modeled effects of soil acidification on long-term ecological and economic outcomes for managed forests in the Adirondack region (USA)

    USGS Publications Warehouse

    Caputo, Jesse PhD.; Beier, Colin M.; Sullivan, Timothy J.; Lawrence, Gregory B.

    2016-01-01

    Sugar maple (Acer saccharum) is among the most ecologically and economically important tree species in North America, and its growth and regeneration is often the focus of silvicultural practices in northern hardwood forests. A key stressor for sugar maple (SM) is acid rain, which depletes base cations from poorly-buffered forest soils and has been associated with much lower SM vigor, growth, and recruitment. However, the potential interactions between forest management and soil acidification – and their implications for the sustainability of SM and its economic and cultural benefits – have not been investigated. In this study, we simulated the development of 50 extant SM stands in the western Adirondack region of NY (USA) for 100 years under different soil chemical conditions and silvicultural prescriptions. We found that interactions between management prescription and soil base saturation will strongly shape the ability to maintain SM in managed forests. Below 12% base saturation, SM did not regenerate sufficiently after harvest and was replaced mainly by red maple (Acer rubrum) and American beech (Fagus grandifolia). Loss of SM on acid-impaired sites was predicted regardless of whether the shelterwood or diameter-limit prescriptions were used. On soils with sufficient base saturation, models predicted that SM will regenerate after harvest and be sustained for future rotations. We then estimated how these different post-harvest outcomes, mediated by acid impairment of forest soils, would affect the potential monetary value of ecosystem services provided by SM forests. Model simulations indicated that a management strategy focused on syrup production – although not feasible across the vast areas where acid impairment has occurred – may generate the greatest economic return. Although pollution from acid rain is declining, its long-term legacy in forest soils will shape future options for sustainable forestry and ecosystem stewardship in the northern

  16. Mountain Home Well - Photos

    DOE Data Explorer

    Shervais, John

    2012-01-11

    The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberly, and (3) Mountain Home. The Mountain Home drill hole is located along the western plain and documents older basalts overlain by sediment. Data submitted by project collaborator Doug Schmitt, University of Alberta

  17. STRAWBERRY MOUNTAIN WILDERNESS, OREGON.

    USGS Publications Warehouse

    Thayer, T.P.; Stotelmeyer, Ronald B.

    1984-01-01

    The Strawberry Mountain Wilderness extends 18 mi along the crest of the Strawberry Range and comprises about 53 sq mi in the Malheur National Forest, Grant County, Oregon. Systematic geologic mapping, geochemical sampling and detailed sampling of prospect workings was done. A demonstrated copper resource in small quartz veins averaging at most 0. 33 percent copper with traces of silver occurs in shear zones in gabbro. Two small areas with substantiated potential for chrome occur near the northern edge of the wilderness. There is little promise for the occurrence of additional mineral or energy resources in the Strawberry Mountain Wilderness.

  18. Prevalence of acute mountain sickness in the Eastern Alps.

    PubMed

    Mairer, Klemens; Wille, Maria; Bucher, Thomas; Burtscher, Martin

    2009-01-01

    Little information is available on the prevalence of acute mountain sickness (AMS) in the Eastern Alps compared with the Western Alps. Because of differences regarding the populations of mountaineers, we hypothesized that the prevalence differs between the Eastern and Western Alps. Thus, we determined the prevalence and risk factors of AMS at four different altitudes in the Eastern Alps of Austria. Four hundred and thirty-one recreational hikers were studied using questionnaires on the morning of their first night at high altitude. A diagnosis of AMS was based on a Lake Louise Score > or =4, the presence of headache, and at least one additional symptom. Overall 16.2% of the subjects met the criteria for AMS, and the prevalence of AMS increased significantly with altitude (2200 m: 6.9%; 2500 m: 9.1%; 2800 m: 17.4%; 3500 m: 38.0%). Heavy perceived exertion, a history of migraine, the absolute altitude reached, little mountaineering experience, and inadequate water intake (< or =2 L) were independent AMS risk factors. The reported altitude-related AMS prevalence in the Western Alps is 4% to 8% lower compared with that found in this study for the Eastern Alps. In conclusion, the prevalence of AMS is higher in the tourist population of the Eastern Alps compared to the more experienced mountaineers of the Western Alps. Consideration of easily modifiable risk factors such as individual exertion and water intake could markedly reduce AMS and contribute to the enjoyment of mountaineering.

  19. Multi-year wind dynamics around Lake Tanganyika

    NASA Astrophysics Data System (ADS)

    Docquier, D.; Thiery, W.; Lhermitte, S.; van Lipzig, N.

    2016-11-01

    Lake Tanganyika is the second largest freshwater lake in the world by volume and is of prime importance for the regional economy in East Africa. Although the lake is recognized as a key component of the regional climate system, little is known about atmospheric dynamics in its surroundings. To understand this role, we analyze winds around Lake Tanganyika as modeled by a high resolution (7 km) regional climate model (Consortium for Small-scale Modeling in Climate Mode) over the period 1999-2008. Modeled surface wind speed and direction are in very good agreement with high resolution (12.5 km) Quick Scatterometer (QuikSCAT) satellite wind observations during the dry season. Comparison of a control run with a model simulation where all lake pixels are replaced by representative land pixels indicates that mean surface wind speed over Lake Tanganyika almost doubles due to lake presence. Furthermore, a region of higher surface wind speed in the central part of the lake is identified and confirmed by QuikSCAT observations. A combination of wind channeling along valley mountains and wind confluence on the upwind side of the lake is responsible for this speed-up. The lower wind speeds in the rest of the lake result from blocked conditions due to more pronounced orography. Finally, the model captures a zone of higher wind speed at around 2 km height, associated with the low-level Somali jet. These results demonstrate that high resolution climate modeling allows a detailed understanding of wind dynamics in the vicinity of Lake Tanganyika.

  20. Microseisms from the Great Salt Lake

    NASA Astrophysics Data System (ADS)

    Goddard, K. J.; Koper, K. D.; Burlacu, V.

    2014-12-01

    Dept. of Geology and Geophysics, University of Utah, Salt Lake City, UT, 84112, USA We performed frequency-dependent polarization and power analysis on continuous ambient seismic energy recorded by broadband seismic stations that were part of the Utah Regional Seismic Network (UU) for the years of 2001-2013. The number of broadband seismometers increased from 10 to 28 in this time period. As expected, at all 28 stations the single and double frequency peaks caused by microseisms were observed in the range of 3-20 s. At four of the stations located around the Great Salt Lake (BGU, HVU, NOQ, and SPU) an additional noise peak was intermittently observed in the period range of 0.8-1.2 s. This noise peak was strongest at SPU, a station located on the tip of a peninsula jutting into the lake from the north, and weakest at NOQ, a station located a few kilometers south of the lake in the Oquirrh Mountains. The noise peaks occur in both daytime and nighttime, and have durations lasting from a couple of hours to multiple days. They occur more frequently in the spring, summer, and fall, and less commonly in the winter. The occurrences of noise peaks in the summer show a day night pattern and seem to reach a peak during the night. The time dependence of this 1-s seismic noise was compared to records of wind speed measured at 1-hr intervals from nearby meteorological stations run by the NWS, and to lake level gage height measurements made by the USGS. Correlations with wind speed and lake level were done for every month of the year in 2013. Results showed that the correlations with wind varied throughout the year from a high of 0.49 in November to a low of 0.20 in the month of January. The correlation with lake level also varied throughout the year and the strongest correlation was found in the month of December with a correlation of 0.43. While these correlation values are statistically significant, neither wind nor lake level can completely explain the seismic observations

  1. Glacial Lake Expansion in the Central Himalayas by Landsat Images, 1990–2010

    PubMed Central

    Nie, Yong; Liu, Qiao; Liu, Shiyin

    2013-01-01

    Glacial lake outburst flood (GLOF) is a serious hazard in high, mountainous regions. In the Himalayas, catastrophic risks of GLOFs have increased in recent years because most Himalayan glaciers have experienced remarkable downwasting under a warming climate. However, current knowledge about the distribution and recent changes in glacial lakes within the central Himalaya mountain range is still limited. Here, we conducted a systematic investigation of the glacial lakes within the entire central Himalaya range by using an object-oriented image processing method based on the Landsat Thematic Mapper (TM) or Enhanced Thematic Mapper (ETM) images from 1990 to 2010. We extracted the lake boundaries for four time points (1990, 2000, 2005 and 2010) and used a time series inspection method combined with a consistent spatial resolution of Landsat images that consistently revealed lake expansion. Our results show that the glacial lakes expanded rapidly by 17.11% from 1990 to 2010. The pre-existing, larger glacial lakes, rather than the newly formed lakes, contributed most to the areal expansion. The greatest expansions occurred at the altitudinal zones between 4800 m and 5600 m at the north side of the main Himalayan range and between 4500 m and 5600 m at the south side, respectively. Based on the expansion rate, area and type of glacial lakes, we identified 67 rapidly expanding glacial lakes in the central Himalayan region that need to be closely monitored in the future. The warming and increasing amounts of light-absorbing constituents of snow and ice could have accelerated the melting that directly affected the glacial lake expansion. Across the main central Himalayas, glacial lakes at the north side show more remarkable expansion than those at the south side. An effective monitoring and warning system for critical glacial lakes is urgently needed. PMID:24376778

  2. Glacial lake expansion in the central Himalayas by Landsat images, 1990-2010.

    PubMed

    Nie, Yong; Liu, Qiao; Liu, Shiyin

    2013-01-01

    Glacial lake outburst flood (GLOF) is a serious hazard in high, mountainous regions. In the Himalayas, catastrophic risks of GLOFs have increased in recent years because most Himalayan glaciers have experienced remarkable downwasting under a warming climate. However, current knowledge about the distribution and recent changes in glacial lakes within the central Himalaya mountain range is still limited. Here, we conducted a systematic investigation of the glacial lakes within the entire central Himalaya range by using an object-oriented image processing method based on the Landsat Thematic Mapper (TM) or Enhanced Thematic Mapper (ETM) images from 1990 to 2010. We extracted the lake boundaries for four time points (1990, 2000, 2005 and 2010) and used a time series inspection method combined with a consistent spatial resolution of Landsat images that consistently revealed lake expansion. Our results show that the glacial lakes expanded rapidly by 17.11% from 1990 to 2010. The pre-existing, larger glacial lakes, rather than the newly formed lakes, contributed most to the areal expansion. The greatest expansions occurred at the altitudinal zones between 4800 m and 5600 m at the north side of the main Himalayan range and between 4500 m and 5600 m at the south side, respectively. Based on the expansion rate, area and type of glacial lakes, we identified 67 rapidly expanding glacial lakes in the central Himalayan region that need to be closely monitored in the future. The warming and increasing amounts of light-absorbing constituents of snow and ice could have accelerated the melting that directly affected the glacial lake expansion. Across the main central Himalayas, glacial lakes at the north side show more remarkable expansion than those at the south side. An effective monitoring and warning system for critical glacial lakes is urgently needed.

  3. Predicting the locations of naturally fishless lakes

    USGS Publications Warehouse

    Schilling, Emily Gaenzle; Loftin, C.S.; Degoosh, K.E.; Huryn, Alexander D.; Webster, K.E.

    2008-01-01

    1. Fish have been introduced into many previously fishless lakes throughout North America over the past 100+ years. It is difficult to determine the historical distribution of fishless lakes, however, because these introductions have not always been well-documented. 2. Due to its glacial history and low human population density, the state of Maine (U.S.A.) may host the greatest number of naturally fishless lakes in the northeastern United States. However, less than one-quarter of Maine's 6000+ lakes have been surveyed for fish presence, and no accurate assessments of either the historical or current abundance and distribution of fishless lakes exist. 3. We developed methods to assess the abundance and distribution of Maine's naturally fishless lakes (0.6-10.1 ha). We hypothesized that the historical distribution of fishless lakes across a landscape is controlled by geomorphic and geographic conditions. 4. We used ArcGIS to identify landscape-scale geomorphic and geographic factors (e.g. connectivity, surrounding slope) correlated with fish absence in two geomorphic regions of Maine - the western and interior mountains and the eastern lowlands and foothills. By using readily available geographic information systems data our method was not limited to field-visited sites. We estimated the likelihood that a particular lake is fishless with a stepwise logistic regression model developed for each region. 5. The absence of fish from western lakes is related to altitude (+), minimum percent slope in the 500 m buffer (+), maximum percent slope in the 500 m buffer (+) and percent cover of herbaceous-emergent wetland in 1000 m buffer (-). The absence of fish from eastern lakes is related to the lack of a stream within 50 m of the lake. 6. The models predict that a total of 4% (131) of study lakes in the two regions were historically fishless, with the eastern region hosting a greater proportion than the western region. 7. We verified the model predictions with two

  4. Bighorn sheep response to road-related disturbances in Rocky Mountain National Park, Colorado

    USGS Publications Warehouse

    Keller, B.J.; Bender, L.C.

    2007-01-01

    Bighorn sheep (Ovis canadensis) use of Sheep Lakes mineral site, Rocky Mountain National Park, Colorado, USA, has decreased since 1996. Officials were concerned that human disturbance may have been contributing to this decline in use. We evaluated effects of vehicular traffic and other road-related disturbance on bighorn use of Sheep Lakes in the summers of 2002 and 2003. We found that the time and number of attempts required by bighorn to reach Sheep Lakes was positively related to the number of vehicles and people present at Sheep Lakes. Further, the number of bighorn individuals and groups attempting to visit Sheep Lakes were negatively affected by disturbance associated with the site. The number of vehicles recorded the hour before bighorn tried to access Sheep Lakes best predicted an animal's failure to cross Fall River Road and reach Sheep Lakes. We conclude that human and road-related disturbance at Sheep Lakes negatively affected bighorn use of the mineral site. Because Sheep Lakes may be important for bighorn sheep, especially for lamb production and survival, the negative influence of disturbance may compromise health and productivity of the Mummy Range bighorn sheep.

  5. Review Article: Lake and breach hazard assessment for moraine-dammed lakes: an example from the Cordillera Blanca (Peru)

    NASA Astrophysics Data System (ADS)

    Emmer, A.; Vilímek, V.

    2013-06-01

    Glacial lake outburst floods (GLOFs) and related debris flows represent a significant threat in high mountainous areas across the globe. It is necessary to quantify this threat so as to mitigate their catastrophic effects. Complete GLOF hazard assessment incorporates two phases: the probability of water release from a given glacial lake is estimated through lake and breach hazard assessment while the endangered areas are identified during downstream hazard assessment. This paper outlines a number of methods of lake and breach hazard assessment, which can be grouped into three categories: qualitative, of which we outline eight; semi-quantitative, of which we outline two; and quantitative, of which we outline three. It is considered that five groups of critical parameters are essential for an accurate regionally focused hazard assessment method for moraine-dammed lakes in the Cordillera Blanca. These comprise the possibility of dynamic slope movements into the lake, the possibility of a flood wave from a lake situated upstream, the possibility of dam rupture following a large earthquake, the size of the dam freeboard (or ratio of dam freeboard), and a distinction between natural dams and those with remedial work. It is shown that none of the summarised methods uses all these criteria with, at most, three of the five considered by the outlined methods. A number of these methods were used on six selected moraine-dammed lakes in the Cordillera Blanca: lakes Quitacocha, Checquiacocha, Palcacocha, Llaca, Rajucolta, and Tararhua. The results have been compared and show that each method has certain advantages and disadvantages when used in this region. These methods demonstrate that the most hazardous lake is Lake Palcacocha.

  6. Invasive salmonids and lake order interact in the decline of puye grande Galaxias platei in western Patagonia lakes.

    PubMed

    Correa, Cristian; Hendry, Andrew P

    2012-04-01

    Salmonid fishes, native to the northern hemisphere, have become naturalized in many austral countries and appear linked to the decline of native fishes, particularly galaxiids. However, a lack of baseline information and the potential for confounding anthropogenic stressors have led to uncertainty regarding the association between salmonid invasions and galaxiid declines, especially in lakes, as these have been much less studied than streams. We surveyed 25 lakes in the Aysén region of Chilean Patagonia, including both uninvaded and salmonid-invaded lakes. Abundance indices (AI) of Galaxias platei and salmonids (Salmo trutta and Oncorhynchus mykiss) were calculated using capture-per-unit-effort data from gillnets, minnow traps, and electrofishing. We also measured additional environmental variables, including deforestation, lake morphometrics, altitude, and hydrological position (i.e., lake order). An information-theoretic approach to explaining the AI of G. platei revealed that by far the strongest effect was a negative association with the AI of salmonids. Lake order was also important, and using structural equation modeling, we show that this is an indirect effect naturally constraining the salmonid invasion success in Patagonia. Supporting this conclusion, an analysis of an independent data set from 106 mountain lakes in western Canada showed that introduced salmonids are indeed less successful in low-order lakes. Reproductive failure due to insufficient spawning habitat and harsh environmental conditions could be the cause of these limits to salmonid success. The existence of this effect in Chilean Patagonia suggests that low-order lakes are likely to provide natural ecological refugia for G. platei. Finally, pristine, high-order lakes should be actively protected as these have become rare and irreplaceable unspoiled references of the most diverse, natural lake ecosystems in Patagonia.

  7. The Strongest Mountain

    ERIC Educational Resources Information Center

    Monnes, Colleen

    2004-01-01

    The article describes an activity for the author's fifth-grade students called "build the strongest mountain." To them, it was not a lesson--it was a challenge. To the author, it was an activity that turned a run-of-the-mill Earth science unit into a terrific opportunity for students to demonstrate their knowledge of erosion and develop…

  8. The Mountaineer Minority

    ERIC Educational Resources Information Center

    Egerton, John; Gaillard, Frye

    1974-01-01

    Discusses the new Appalachian movement, based on the assumption that mountain people are a distinct and maligned cultural minority; the people of Appalachia, white, black and red, have begun to strike back against the dam-builders, strip-miners, and others they say are gouging out the region's mineral resources by the cheapest means possible no…

  9. Rocky Mountain High.

    ERIC Educational Resources Information Center

    Hill, David

    2001-01-01

    Describes Colorado's Eagle Rock School, which offers troubled teens a fresh start by transporting them to a tuition- free campus high in the mountains. The program encourages spiritual development as well as academic growth. The atmosphere is warm, loving, structured, and nonthreatening. The article profiles several students' experiences at the…

  10. Rocky Mountain Spotted Fever.

    PubMed

    Phillips, Jennan

    2017-01-01

    The tick-borne disease Rocky Mountain spotted fever (RMSF) can have deadly outcomes unless treated appropriately, yet nonspecific flu-like symptoms complicate diagnosis. Occupational health nurses must have a high index of suspicion with symptomatic workers and recognize that recent recreational or occupational activities with potential tick exposure may suggest RMSF.

  11. DOE's Yucca Mountain Studies.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC.

    This booklet is about the disposal of high-level nuclear waste in the United States with a particular focus on Yucca Mountain, Nevada as a repository site. Intended for readers who do not have a technical background, the booklet discusses why scientists and engineers think high-level nuclear waste may be disposed of safely underground. An…

  12. An Assessment of Glacial Contributions to Lake Dynamics across the Tibetan Plateau since the Late Pleistocene

    NASA Astrophysics Data System (ADS)

    Sheng, Y.

    2014-12-01

    The Tibetan Plateau is one of the world's most vulnerable areas to global warming, and is home of the world's largest group of mountain glaciers and high-altitude lakes. These lakes in general have shrunk significantly since the late Pleistocene, and are currently continuing to experience changes in their distribution and inundation area. In the meantime, Tibetan glaciers have also gone through dramatic changes as evidenced by paleo glacial relics and recent accelerated melting. The paper provides a regional-scale systematic assessment of both paleo and contemporary lake changes across the plateau using geo-spatial information and optically stimulated luminescence (OSL) dating technologies. Using high-resolution satellite imagery of the plateau together with topographic data, this research recovered paleo lake extents for hundreds of contemporary lakes with visible paleo shore relics and estimated the amount of paleo lake shrinkage at regional scales. Both the basin-based water mass balance analysis using glacier/lake sizes and OSL dating of paleo shores suggest that paleo glaciers played a crucial role in the observed paleo lake shrinkage. Recent ~40 year lake dynamics was monitored by tracking thousands of Tibetan lakes using hundreds of satellite images. The results reveal that the overall total lake area has increased by ~26% between 1976 and 2009. The detected lake dynamics exhibit a strong spatial pattern generally but with local variations. The climate change and its regional glacier variations explain the general trend and the regional patterns of lake dynamics, respectively. The glacier mass monitored by GRACE satellites suggests a thinning trend over the past 12 years in the south while a gaining along the northern rim of the plateau. Basin-based analysis identifies glacial impacts on lake dynamics and explains many local variations. It can be concluded that glaciers play an important role in detected paleo as well as recent lake changes, and will

  13. Lake Nasser and Toshka Lakes, Egypt

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Lake Nasser (center) and the Toshka Lakes (center left) glow emerald green and black in this MODIS true-color image acquired March 8, 2002. Located on and near the border of Egypt and Norther Sudan, these lakes are an oasis of water in between the Nubian (lower right) and Libyan Deserts (upper left). Also visible are the Red Sea (in the upper right) and the Nile River (running north from Lake Nasser). Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC