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Sample records for adirondack mountain lakes

  1. 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.

  2. 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.

  3. 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)

  4. 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...

  5. 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

  6. Nitrogen biogeochemistry in the Adirondack Mountains of New York: hardwood ecosystems and associated surface waters.

    PubMed

    Mitchell, Myron J; Driscoll, Charles T; Inamdar, Shreeram; McGee, Greg G; Mbila, Monday O; Raynal, Dudley J

    2003-01-01

    Studies on the nitrogen (N) biogeochemistry in Adirondack northern hardwood ecosystems were summarized. Specific focus was placed on results at the Huntington Forest (HFS), Pancake-Hall Creek (PHC), Woods Lake (WL), Ampersand (AMO), Catlin Lake (CLO) and Hennessy Mountain (HM). Nitrogen deposition generally decreased from west to east in the Adirondacks, and there have been no marked temporal changes in N deposition from 1978 through 1998. Second-growth western sites (WL, PHC) had higher soil solution NO(3-) concentrations and fluxes than the HFS site in the central Adirondacks. Of the two old-growth sites (AMO and CLO), AMO had substantially higher NO(3-) concentrations due to the relative dominance of sugar maple that produced litter with high N mineralization and nitrification rates. The importance of vegetation in affecting N losses was also shown for N-fixing alders in wetlands. The Adirondack Manipulation and Modeling Project (AMMP) included separate experimental N additions of (NH4)2SO4 at WL, PHC and HFS and HNO3 at WL and HFS. Patterns of N loss varied with site and form of N addition and most of the N input was retained. For 16 lake/watersheds no consistent changes in NO(3-) concentrations were found from 1982 to 1997. Simulations suggested that marked NO(3-) loss will only be manifested over extended periods. Studies at the Arbutus Watershed provided information on the role of biogeochemical and hydrological factors in affecting the spatial and temporal patterns of NO(3-) concentrations. The heterogeneous topography in the Adirondacks has generated diverse landscape features and patterns of connectivity that are especially important in regulating the temporal and spatial patterns of NO(3-) concentrations in surface waters.

  7. 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

  8. 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...

  9. 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.

  10. 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.

  11. Hydrologic data from the integrated lake-watershed acidification study in the west-central Adirondack Mountains, New York : October 1977 through January 1982

    USGS Publications Warehouse

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

    1987-01-01

    Hydrologic data were collected from three forested headwater lake watersheds in Herkimer and Hamilton Counties from October 1977 through early January 1982 as part of the Integrated Lake-Watersheds Acidification Study (ILWAS). ILWAS was established in 1977 to determine why these lakes differ in pH when all receive equal amounts of acidic atmospheric deposition. Woods Lake is acidic (pH ranges from 4 to 5), Panther Lake is neutral (pH ranges from 5 to 7.5), and Sagamore Lake is intermediate (pH ranges from 5 to 6). The data tabulated herein include discharge at the three lake outlets and in a tributary to each lake; lake-water stage at each lake; chemical quality of lake water, including total concentrations of zinc, iron, manganese, and lead, at each lake outlet and at Lost Brook (a tributary to Sagamore Lake); groundwater stage from 29 wells; major ion concentrations of groundwater from 22 of these wells; temperature of soil from three depths at one site in each watershed; soil-moisture tension at three depths at eight sites - four in the neutral-lake basin, three in the acidic-lake basin , and one in the intermediate-lake basin; and average snowpack depths and water equivalents at approximately 20 snow-course sites in each basin for three sampling periods during the 1979-80 winter. (USGS)

  12. 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.

  13. Blue Mountain Lake, New York, earthquake of October 7, 1983.

    USGS Publications Warehouse

    Wendt, G.

    1984-01-01

    The October 7 earthquake near Blue Mountain Lake in the central Adirondack Mountains registered a preliminary Richter magnitude of 5.2. It was widely felt throughout the Northeastern United States and Canada and occurred in an area that has been periodically shaken by earthquakes throughout recorded history. Since 1737, at least 346 felt earthquakes have occurred in New York; an earthquake of similar magnitude last shook the Blue Mountain Lake area on June 9, 1975.    

  14. Distribution of epipelic algal communities in an oligotrophic Adirondack lake

    SciTech Connect

    Roberts, D.A.

    1987-01-01

    The biovolume and species composition of algae on the sediment along depth gradients were determined before and after artificial neutralization of an oligotrophic lake in the Adirondack Park in New York State. The epipelic algal community of Woods Lake (Herkimer Co., NY) was dominated by diatoms and cyanobacteria prior to and following liming. Distinct depth-zonation patterns of community composition were evident and unaffected by the base (CaCO/sub 3/) addition. Prior to liming, there was an increase in total algal biovolume with depth, due to the presence of a dense cyanobacterial community on the sediments in deeper water (5 m to 8 m). This mat was dominated by a single species of cyanobacteria, Hapalosiphon pumilus, which accounted for the late summer maximum in total biovolume at 7 m. The shallower (1 m-4 m) epipelic communities were dominated by diatoms, which showed a spring maximum in total biovolume. Woods Lake, one of the sites of the Lake Acidification Mitigation Project (LAMP), was treated with CaCO/sub 3/ on May 31, 1985. Among other physical and chemical changes, the base treatment increased the pH from 5.0 to above 9.0, ANC from 0 to > 400 ..mu..eq/L. Water clarity was reduced immediately after liming and cleared gradually over an eight-week period.

  15. U-Pb zircon geochronology of the Adirondack Mountains and implications for their geologic evolution

    SciTech Connect

    McLelland, J. ); Chiarenzelli, J. ); Whitney, P.; Ischsen, Y. )

    1988-10-01

    U-Pb zircon studies of metamorphosed igneous rocks in the Adirondack Mountains have yielded preliminary ages within the range 1420-990 Ma. Several geochronologically and geochemically distinct episodes of igneous intrusion and at least one pre-granulite facies dynamothermal metamorphic event are documented. This information is consistent with recent field and geochronological studies throughout the Grenville province and suggests that a complex sequence of events occurred in the Adirondack Mountains prior to the widespread deformation and metamorphism commonly attributed to the {approximately} 1100-1000 Ma Ottawan phase of the Grenvillian orogenic cycle.

  16. 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.

  17. 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)....

  18. Analysis of ambient, precipitation-weighted, and lake sulfate concentrations in the Adirondack region of New York.

    PubMed

    Civerolo, Kevin; Brankov, Elvira; Rao, S Trivikrama; Roy, Karen; Lewis, Preston; Galvin, Philip

    2003-01-01

    AbstractIt is well known that many ecosystems in the eastern United States, including the Adirondack Mountain region of New York, are particularly sensitive to acidic deposition because the soils and lakes in the region tend to have low values of base saturation and acid neutralizing capacity, respectively [e.g. Environ Sci Policy, 1 (1998), 185]. To facilitate tracking the impacts of anthropogenic emissions on air quality, acidic deposition, and surface water quality, the National Atmospheric Deposition Program, New York State Department of Environmental Conservation, and Adirondack Lake Survey Corporation have been monitoring ambient sulfur dioxide and aerosol sulfate levels, and anion and cation concentrations in wet deposition and lake water over the past few decades. In this paper, we discuss the seasonality and year-to-year variability, and illustrate some of the complexities in estimating temporal trends in these data. The periods of analysis extended through 2000, beginning in 1991 for the ambient air quality data, 1978 for the wet deposition data, and 1982 for the lake water quality data. While the lake water SO4(2-) concentrations appear to be decreasing gradually, the air concentration data appear to have changed abruptly in the 1990s and the precipitation-weighted concentrations exhibited both gradual and sharp decreases during the same period.

  19. Chemical response of lakes in the Adirondack Region of New York to declines in acidic deposition.

    PubMed

    Driscoll, Charles T; Driscoll, Kimberley M; Roy, Karen M; Mitchell, Myron J

    2003-05-15

    Long-term changes in the chemistry of wet deposition and lake water were investigated in the Adirondack Region of New York. Marked decreases in concentrations of SO4(2-) and H+ in wet deposition have occurred at two sites since the late 1970s. These decreases are consistent with long-term declines in emissions of sulfur dioxide (SO2) in the eastern United States. Changes in wet NO3- deposition and nitrogen oxides (NOx) emissions have been minor over the same interval. Virtually all Adirondack Lakes have shown marked decreases in concentrations of SO4(2-), which coincide with decreases in atmospheric S deposition. Concentrations of NO3- have also decreased in several Adirondack lakes. As atmospheric N deposition has not changed over this period, the mechanism contributing to this apparent increase in lake/watershed N retention is not evident. Decreases in concentrations of SO4(2-) + NO3- have resulted in increases in acid-neutralizing capacity (ANC) and pH and resulted in a shift in the speciation of monomeric Al from toxic inorganic species toward less toxic organic forms in some lakes. Nevertheless, many lakes continue to exhibit pH values and concentrations of inorganic monomeric Al that are critical to aquatic biota. Extrapolation of rates of ANC increase suggests that the time frame of chemical recovery of Adirondack Lakes will be several decades if current decreases in acidic deposition are maintained.

  20. 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 ...

  1. 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.

  2. Detailed studies of selected, well-exposed fracture zones in the Adirondack Mountains dome, New York

    SciTech Connect

    Wiener, R.W.; Isachsen, Y.W.

    1987-01-01

    The Adirondack Mountains constitute a relatively young (Mesozoic, Cenozoic) dome on the craton. The dome is undergoing contemporary uplift, based on geodetic releveling, and is seismically active. The breached dome provides a very large window through Paleozoic cover and thus permits ground study of the fracture systems that characterize the seismogenic basement and influence the patterns of brittle deformation that are found in overlying Paleozoic rocks of the platform. The predominant fracture zones are linear valleys that trend NNE to NE, parallel to the long axis of the dome. The 36 field studies of the lineament segments discussed in this report suggest that the prominent NE to NNE fracture systems in the eastern Adirondacks are dominantly high angle faults down-stepped to the east, whereas those in the central Adirondacks are dominantly zero-displacement crackle zones. The origin of these features is related to the rapid uplift of the Adirondack dome. Similar features can be expected to be found in other areas of domal uplift or rapid regional uplift.

  3. Fish population losses from Adirondack Lakes: The role of surface water acidity and acidification

    NASA Astrophysics Data System (ADS)

    Baker, Joan P.; Warren-Hicks, William J.; Gallagher, James; Christensen, Sigurd W.

    1993-04-01

    Changes over time in the species composition of fish communities in Adirondack lakes were assessed to determine (1) the approximate numbers offish populations that have been lost and (2) the degree to which fish population losses may have resulted from surface water acidification and acidic deposition. Information on the present-day status offish communities was obtained by the Adirondack Lakes Survey Corporation, which surveyed 1469 Adirondack lakes in 1984-1987 (53% of the total ponded waters in the Adirondack ecological zone). Two hundred and ninety-five of these lakes had been surveyed in 1929-1934 during the first statewide biological survey; 720 had been surveyed in one or more years prior to 1970. Sixteen to 19% of the lakes with adequate historical data appeared to have lost one or more fish populations as a result of acidification. Brook trout and acid-sensitive minnow species had experienced the most widespread effects. Populations of brook trout and acid-sensitive minnows had been lost apparently as a result of acidification from 11% and 19%, respectively, of the lakes with confirmed historical occurrence of these taxa. By contrast, fish species that tend to occur primarily in lower elevation and larger lakes, such as largemouth and smallmouth bass and brown trout, have experienced little to no documented adverse effects. Lakes that were judged to have lost fish populations as a result of acidification had significantly lower; pH and, in most cases, also had higher estimated concentrations of inorganic aluminum and occurred at higher elevations than did lakes with the fish species still present. No other lake characteristics were consistently associated with fish population losses attributed to acidification. The exact numbers and proportions of fish populations affected could not be determined because of limitations on the quantity and quality of historical data. Lakes for which we had adequate historical data to assess long-term trends in fish

  4. 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.

  5. 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.

  6. 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

  7. Microbiological survey of Adirondack lakes with various pH values

    SciTech Connect

    Boylen, C.W.; Shick, M.O.; Roberts, D.A.

    1983-05-01

    Many of the lakes in the Adirondack region of New York State are particularly sensitive to high H/sup +/ inputs from acidic deposition. Nine high-altitude oligotrophic Adirondack lakes having water of pH 4.3 to 7.0 were surveyed for total bacterial numbers and possible adaptation of the microbial communities to environmental pH. The number of heterotrophic bacteria from water samples recoverable on standard plate count agar were low (10 to 1000 per ml) for most of the lakes. Sediment aerobic heterotrophs recovered on standard plate count agar ranged from 14,000 to 1,300,000 per g of sediment. Low density values were consistent with the oligotrophic nature of all the lakes surveyed. There were no apparent differences in numbers of bacteria originally isolated at pH 5.0 and pH 7.0 between circumneutral lakes (pH 6.0) and acidic lakes (pH 5.0). A chi-square contingency test clearly showed (P 0.005) that two distinct heterotrophic populations had been originally isolated at pH 5.0 and pH 7.0, although there is undoubtedly some overlap between the two populations. 35 references, 5 figures, 3 tables.

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. Atmospheric Science Research at the Whiteface Mountain Adirondack High Peaks Observatory

    NASA Astrophysics Data System (ADS)

    Schwab, J. J.; Brandt, R. E.; Casson, P.; Demerjian, K. L.; Crandall, B. A.

    2014-12-01

    The Atmospheric Sciences Research Center established an atmospheric observatory at Whiteface Mountain in the Adirondacks in 1961. The current mountain top observatory building was built by the University at Albany in 1969-70 and the New York State Department of Environmental Conservation (DEC) began ozone measurements at this summit location in 1973. Those measurements continue to this day and constitute a valuable long term data record for tropospheric ozone in the northeastern U.S. The elevation of the summit is 1483 m above sea level, and is roughly 90 m above the tree line in this location. With a mean cloud base height of less than 1100 m at the summit, it is a prime location for cloud research. The research station headquarters, laboratories, offices, and a second measurement site are located at the Marble Mountain Lodge, perched on a shoulder northeast of the massif at an elevation of 604 m above sea level. Parameters measured at the site include meteorological variables, trace gases, precipitation chemistry, aerosol mass and components, and more. Precipitation and cloud chemistry has a long history at the lodge and summit locations, respectively, and continues to this day. Some data from the 40-year record will be shown in the presentation. In the late 1980's the summit site was outfitted with instrumentation to measure oxides of nitrogen and other ozone precursors. Measurements of many of these same parameters were added at the lodge site and continue to this day. In this poster we will give an overview of the Whiteface Mountain Observatory and its two measurement locations. We will highlight the parameters currently being measured at our sites, and indicate those measured by ASRC, as well as those measured by other organizations. We will also recap some of the historical activities and measurement programs that have taken place at the site, as alluded to above. Also included will be examples of the rich archive of trends data for gas phase species

  13. 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

  14. 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

  15. 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.

  16. 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.

  17. 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. PMID:24102084

  18. 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.

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

    PubMed

    Lawrence, Gregory B; Dukett, James E; Houck, Nathan; Snyder, Phil; Capone, Sue

    2013-07-01

    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.

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

    PubMed

    Lawrence, Gregory B; Dukett, James E; Houck, Nathan; Snyder, Phil; Capone, Sue

    2013-07-01

    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. PMID:23751119

  1. Responses of 20 lake-watersheds in the Adirondack region of New York to historical and potential future acidic deposition.

    PubMed

    Zhou, Qingtao; Driscoll, Charles T; Sullivan, Timothy J

    2015-04-01

    Critical loads (CLs) and dynamic critical loads (DCLs) are important tools to guide the protection of ecosystems from air pollution. In order to quantify decreases in acidic deposition necessary to protect sensitive aquatic species, we calculated CLs and DCLs of sulfate (SO4(2-))+nitrate (NO3-) for 20 lake-watersheds from the Adirondack region of New York using the dynamic model, PnET-BGC. We evaluated lake water chemistry and fish and total zooplankton species richness in response to historical acidic deposition and under future deposition scenarios. The model performed well in simulating measured chemistry of Adirondack lakes. Current deposition of SO4(2-)+NO3-, calcium (Ca2+) weathering rate and lake acid neutralizing capacity (ANC) in 1850 were related to the extent of historical acidification (1850-2008). Changes in lake Al3+ concentrations since the onset of acidic deposition were also related to Ca2+ weathering rate and ANC in 1850. Lake ANC and fish and total zooplankton species richness were projected to increase under hypothetical decreases in future deposition. However, model projections suggest that lake ecosystems will not achieve complete chemical and biological recovery in the future.

  2. 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.

  3. 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.

  4. 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.

  5. Microbiological Survey of Adirondack Lakes with Various pH Values

    PubMed Central

    Boylen, Charles W.; Shick, Marcy O.; Roberts, Deborah A.; Singer, Robert

    1983-01-01

    Nine high-altitude oligotrophic Adirondack lakes in upstate New York having water of pH 4.3 to 7.0 were surveyed for total bacterial numbers and possible adaptation of the microbial communities to environmental pH. The number of heterotrophic bacteria from water samples recoverable on standard plate count agar were low (101 to 103 per ml) for most of the lakes. Acridine orange direct counts were approximately two orders of magnitude higher than plate counts for each lake. Sediment aerobic heterotrophs recovered on standard plate count agar ranged from 1.4 × 104 to 1.3 × 106 per g of sediment. Direct epifluorescence counts of bacteria in sediment samples ranged from 3.0 × 106 to 1.4 × 107 per g. Low density values were consistent with the oligotrophic nature of all the lakes surveyed. There were no apparent differences in numbers of bacteria originally isolated at pH 5.0 and pH 7.0 between circumneutral lakes (pH > 6.0) and acidic lakes (pH < 5.0). Approximately 1,200 isolates were recultured over a range of pH from 3.0 to 7.0. Regardless of the original isolation pH (pH 5.0 or pH 7.0), less than 10% of the isolates grew at pH < 5.0. Those originally isolated at pH 5.0 also grew at pH 6.0 and 7.0. Those originally isolated at pH 7.0 preferred pH 7.0, with 98% able to grow at pH 6.0 and 44% able to grow at pH 5.0. A chi-square contingency test clearly showed (P < 0.005) that two distinct heterotrophic populations had been originally isolated at pH 5.0 and pH 7.0, although there is undoubtedly some overlap between the two populations. PMID:16346291

  6. 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

  7. Development of a total maximum daily load (TMDL) for acid-impaired lakes in the Adirondack region of New York

    NASA Astrophysics Data System (ADS)

    Fakhraei, Habibollah; Driscoll, Charles T.; Selvendiran, Pranesh; DePinto, Joseph V.; Bloomfield, Jay; Quinn, Scott; Rowell, H. Chandler

    2014-10-01

    Acidic deposition has impaired acid-sensitive surface waters in the Adirondack region of New York by decreasing pH and acid neutralizing capacity (ANC). In spite of air quality programs over past decades, 128 lakes in the Adirondacks were classified as “impaired” under Section 303(d) of the Clean Water Act in 2010 due to elevated acidity. The biogeochemical model, PnET-BGC, was used to relate decreases in atmospheric sulfur (S) and nitrogen (N) deposition to changes in lake water chemistry. The model was calibrated and confirmed using observed soil and lake water chemistry data and then was applied to calculate the maximum atmospheric deposition that the impaired lakes can receive while still achieving ANC targets. Two targets of ANC were used to characterize the recovery of acid-impaired lakes: 11 and 20 μeq L-1. Of the 128 acid-impaired lakes, 97 currently have ANC values below the target value of 20 μeq L-1 and 83 are below 11 μeq L-1. This study indicates that a moderate control scenario (i.e., 60% decrease from the current atmospheric S load) is projected to recover the ANC of lakes at a mean rate of 0.18 and 0.05 μeq L-1 yr-1 during the periods 2022-2050 and 2050-2200, respectively. The total maximum daily load (TMDL) of acidity corresponding to this moderate control scenario was estimated to be 7.9 meq S m-2 yr-1 which includes a 10% margin of safety.

  8. Deep crustal deformation by sheath folding in the Adirondack Mountains, USA

    NASA Technical Reports Server (NTRS)

    Mclelland, J. M.

    1988-01-01

    As described by McLelland and Isachsen, the southern half of the Adirondacks are underlain by major isoclinal (F sub 1) and open-upright (F sub 2) folds whose axes are parallel, trend approximately E-W, and plunge gently about the horizontal. These large structures are themselves folded by open upright folds trending NNE (F sub 3). It is pointed out that elongation lineations in these rocks are parallel to X of the finite strain ellipsoid developed during progressive rotational strain. The parallelism between F sub 1 and F sub 2 fold axes and elongation lineations led to the hypothesis that progressive rotational strain, with a west-directed tectonic transport, rotated earlier F sub 1-folds into parallelism with the evolving elongation lineation. Rotation is accomplished by ductile, passive flow of F sub 1-axes into extremely arcuate, E-W hinges. In order to test these hypotheses a number of large folds were mapped in the eastern Adirondacks. Other evidence supporting the existence of sheath folds in the Adirondacks is the presence, on a map scale, of synforms whose limbs pass through the vertical and into antiforms. This type of outcrop pattern is best explained by intersecting a horizontal plane with the double curvature of sheath folds. It is proposed that sheath folding is a common response of hot, ductile rocks to rotational strain at deep crustal levels. The recognition of sheath folds in the Adirondacks reconciles the E-W orientation of fold axes with an E-W elongation lineation.

  9. 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.

  10. 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

  11. Preliminary Analysis of Borosilicate Minerals in Pegmatitic Leucosomes within Aluminous Granulites at Ledge Mountain, Central Adirondack Highlands, New York

    NASA Astrophysics Data System (ADS)

    Gervais, S. M.; Metzger, E. P.

    2011-12-01

    The borosilicates tourmaline and dumortierite have been identified by polarized light microscopy and electron microprobe analysis in anatectic abyssal-type pegmatites within aluminum-rich granulite-facies migmatites at Ledge Mountain, Central Adirondacks, New York. No other boron-bearing minerals are found in these rocks, and neither borosilicate has been found in the adjacent host gneiss. Tourmaline is ubiquitous in the granulite and upper amphibolite-facies metamorphic rocks of the Central Adirondacks. Dumortierite has been reported from pegmatites of the Batchellerville Province of the Southern Adirondacks, approximately 66 km to the southeast of Ledge Mountain, but not previously at this locality. The tourmaline is alkali dravite-schorl with Mg# = 0.49- 0.53. It is present as anhedral grains less than 2 mm wide intergrown with perthitic microcline and quartz, and as euhedral megacrysts several centimeters in diameter. The dumortierite is strongly pleochroic, ranging from deep indigo blue and violet to colorless. Two strikingly different habits of dumortierite coexist within centimeters of one another in the same sample: bundles of fine prisms less than a few tenths of a millimeter across, and larger granular intergrowths with quartz and chlorite. Apatite and xenotime are also present in both leucosomes and melanosomes, indicating phosphate-enrichment and yttrium in the granulites. According to experimentally determined fields of stability for boron-bearing minerals, the presence of tourmaline and dumortierite and absence of other boron-bearing minerals, especially prismatine, in the pegmatites is consistent with estimated metamorphic conditions of approximately 695-770°C and 7.4-8.2 kbar, as previously determined for this locality using garnet-biotite thermometry and GASP barometry (Boone, 1978). The presence of borosilicates in the leucosomes of these migmatites and the conspicuous lack of them in the paleosome may suggest destabilization of boron

  12. Patterns of epipelic algal distribution in an acidic adirondack lake. [Hapalosiphon pumilus; Fragilaria acidobiontica; Navicula tenuicephala; Navicula subtilissima

    SciTech Connect

    Roberts, D.A.; Boylen, C.W.

    1988-06-01

    The biovolume and species composition of epipelic algae along sediment depth gradients were sampled seasonally in an acidic oligotrophic lake in the Adirondack Park in New York State. The epipelic algal community of Woods Lake (Herkimer Co., NY) was dominated by diatoms and cyanobacteria. Distinct depth zonation patterns of community composition were evident. Total algal biovolume increased with depth due to a dense cyanobacterial mat on the sediments in deeper water (5-8 m). This mat was dominated by a single species of cyanobacteria, Hapalosiphon pumilus (Kuetz). Kirchner, which accounted for the later summer maximum in total biovolume at 7 m. The shallower (1-4 m) epipelic communities were dominated by diatoms, which showed a spring maximum in total biovolume and were dominated by Fragilaria acidobiontica Charles, Navicula tenuicephala Hust, and N. subtilissima Cl.

  13. Age and petrogenesis of the Diana Complex, Adirondack Mountains, New York

    SciTech Connect

    Grant, N.; Yang, Yingping . Dept. of Geology); Cliff, R. . Dept. of Earth Sciences)

    1992-01-01

    U-Pb zircon data show that the Diana Complex was emplaced 1152[plus minus]12 Ma ago along the Carthage-Colton Mylonite Zone (CCMZ), that marks the boundary between the Adirondack Highlands and the Lowlands. The tectonic setting of the Complex is uncertain because granitoid plutons of the same age were emplaced under syntectonic conditions in the Lowlands, while in the Highlands the same plutons have been viewed as anorogenic. Deformation focused on the CCMZ is reflected in whole-rock Rb-Sr isochron age of 1038[plus minus]97 Ma for the Complex. This resetting is typical of granitoid plutons within a 10 km-wide zone across the CCMZ, but is absent outside this zone elsewhere in the Lowlands. Although the chemical continuity of the Complex with Adirondack mafic rocks of the same presumed age demonstrates that crystal fractionation from a basic parent was a likely origin for the Complex, it is probable the magmas were modified by crustal assimilation. For example, the initial [sup 87]Sr/[sup 86]Sr[sub 1152] values for the Complex (0.7042[plus minus]3) are higher than the same ratios for Adirondack mafic rocks (0.7033[plus minus]6), and one zircon fraction lies to the right of the discordia defined by the other four analyzed fractions. The nature and age of the assimilant may be constrained by a metasedimentary xenolith with a whole-rock Rb-Sr isochron age of 1318[plus minus]15 Ma. Changes in TiO[sub 2] and P[sub 2]O[sub 5] abundances and La/Yb values indicate that the crystallization of both accessory (e.g., Fe-Ti oxides, apatite and zircon) and silicate phases were important in the fractionation of the Diana Complex syenites.

  14. Interpretation of whole-rock Rb-Sr geochronology in the high grade rocks of the Adirondack Mountains, New York

    SciTech Connect

    Yang, Y.; Grant, N.K. . Dept. of Geology)

    1992-01-01

    Published and new Rb-Sr whole-rock isochrons for high grade metaigneous, gneissic and mylonitic rocks from the Adirondack Mountains have been evaluated in two ways. In the first, the Rb-Sr ages are compared to the published U-Pb zircon ages for metaigneous rocks. In the second, the ages are compared with forward modeling that employs Monte Carlo simulation and solid diffusion calculations to determine the probabilities of Rb-Sr resetting under various conditions of channelized and homogeneous fluid flow. The first comparison shows that the Rb-Sr isochrons fall into three groups. The first comprises isochrons of ca. 1050 Ma for mylonitic and metaigneous rocks from the Carthage-Colton Mylonite Zone that separates the Highlands from the Lowlands, and the zone of Trans-Adirondack Structural Discontinuities that separate the southern from the northern Highlands. These ages can be interpreted to the result of complete resetting during the Ottawan phase of the Grenville orogeny. The second group comprises isochrons that are concordant or consistent with the U-Pb zircon ages, and the third group isochrons with ages intermediate between the U-Pb zircon ages and that for high grade metamorphism at 1150 Ma and 1050 Ma in the Lowlands and Highlands respectively. The forward modeling suggests that complete resetting of Rb-Sr isochrons was associated with high fluid/rock ratios (>2) under conditions of homogeneous flow, and that fluid/rock ratios were low (<0.25) in cases where no resetting has occurred. Partial resetting, as can be demonstrated in the Lowlands, requires conditions intermediate between the first two cases or extremely heterogeneous fluid flow. These results show that whole-rock Rb-Sr age determination can recover useful information from high grade rocks, providing the samples are collected from clearly documented tectonic domains.

  15. 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.

  16. 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.

  17. 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.

  18. 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. PMID:26571235

  19. 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.

  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. 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

  2. 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.

  3. 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.

  4. The Carthage-Colton mylonite zone (Adirondack Mountains, New York): The site of a cryptic suture in the Grenville Orogen

    SciTech Connect

    Mezger, K.; Pluijm, B.A. van der; Essene, E.J.; Halliday, A.N. )

    1992-09-01

    U-Pb ages were determined on metamorphic sphenes and monazites from the Late Proterozoic Adirondack Highlands and Lowlands in the vicinity of the Carthage-Colton mylonite zone. Monazites were extracted from metapelites, and sphenes were separated from marbles, calc-silicate gneisses, and granite gneisses in order to determine the timing and the duration of metamorphism as well as the cooling histories for rocks on either side of the mylonite zone. Monazite ages from the Lowlands range from 1,171-1,137 Ma; sphene ages in the Lowlands range from 1,156-1,103 Ma, those from the Highlands immediately to the east of the mylonite zone range from 1,050-982 ma. The ages indicate that the last high-grade metamorphism in the Highlands is ca. 100 m.y. younger than in the Lowlands and that both terranes had separate cooling histories at least until ca. 1,000 Ma. Sphenes from within the Carthage-Colton mylonite zone yield ages of about 1,098 Ma, which are distinct from sphene ages on either side of the shear zone. The mineral ages, structures, and metamorphic histories suggests that the Carthage-Colton mylonite zone is a fundamental tectonic boundary within the Proterozoic Grenville Orogen of North America.

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

    NASA Astrophysics Data System (ADS)

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

    2012-09-01

    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 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, ANCc and NO3- (p = 0.23; 0.24 and 0.20, respectively). Sugar maple basal areas were positively correlated 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.

  6. 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.

  7. Using Critical Loads to Look at Improvements in Acidic Surface Water Conditions since the 1990 Amendments to the Clear Air Act: Case Study Adirondack, NY

    NASA Astrophysics Data System (ADS)

    Lynch, J. A.; Kolian, M. J.; Haeuber, R.

    2008-12-01

    Acid deposition has affected hundreds of lakes and thousands of miles of headwater streams in the Adirondack region of New York State. The diversity of life in these acidic waters has been greatly reduced. The poor buffering capacity of the thin, acidic soils in the Adirondack Mountains makes the lakes and ponds particularly susceptible to acidification. Since the mid-1990's, lakes in the Adirondack region are finally showing signs of recovery. The good news is that emissions of sulfur dioxide and nitrogen oxides have been reduced and as a result acidic deposition of sulfate and nitrate has decreased in surface waters approximately 26 and 13%, respectively. This has led to improvement in the acid neutralizing capacity (ANC) of these water bodies. Although improvement in water quality is a good sign, it does not tell us if a particular lake or a group of lakes have recovered from decades of acidic deposition. However, the critical loads approach does allow for evaluation of whether a water body has reached recovery for acidic deposition. Critical loads and exceedances for lake surface water and acidity were calculated for 187 lakes in the Adirondack region. The Steady-State Water Chemistry (SSWC) model was used to calculate the critical load, relying on water chemistry data from the TIME/LTM network. An ANC threshold of 50 μeq/L was selected for this case study. Exceedances were calculated from deposition for the period before implementation of the Acid Rain program (ARP) (1989-1991) and for the period of 2004-2006 to judge improvements as a result of the ARP. On average, the critical load for lakes in the Adirondack region is 164 meq/m2/yr, while it is 48 meq/m2/yr for the most sensitive lakes (i.e. ANC less than 100 μeq/L). For the period from 2004 to 2006, 65% of the lakes within the TIME/LTM network continued to receive levels of acid deposition that exceeded the lake's critical load down from 72% of lakes before implementation of the Acid Rain Program

  8. 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.

  9. 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

  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

    USGS Publications Warehouse

    Riva-Murray, Karen; Bradley, Paul M.; Chasar, Lia C.; Button, Daniel T.; Brigham, Mark E.; Eikenberry, Barbara C. Scudder; 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 (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

  12. 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.

  13. 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.

  14. Tracking hydrothermal alteration and mineralization in rock-forming and accessory minerals from the Lyon Mountain Granite and related iron oxide apatite (IOA) ores from the Adirondack Mountains, New York State

    NASA Astrophysics Data System (ADS)

    Buchanan, A.; Hanchar, J. M.; Steele-MacInnis, M. J.; Crowley, J. L.; Valley, P. M.; Fisher, C. M.; Fedo, C.; Piccoli, P. M.; Fournelle, J.

    2012-12-01

    The Lyon Mountain granite (LMG) is located in the northeastern Adirondack Mountains in New York State and hosts several low-titanium iron oxide apatite (IOA) ore deposits. The ores are predominately hosted by perthite bearing granite, which has been extensively altered to albite and microcline granite by Na and K metasomatism. This alteration results in several distinct groups of rocks that are dominated by either K or Na addition and a group composed of mixed Na and K addition. The different groups of altered perthite also lie on a trend suggestive of addition of Fe to each, consistent with a secondary mineralization origin. Previous work showed that the host rocks of the IOA ores have zircon with ~1150 Ma cores and 1060-1050 Ma rims and whole grains. This study aims to further constrain the timing of LMG emplacement, subsequent hydrothermal alteration, and Fe mineralization through geochemical analysis of the major, minor, and accessory phases and geochronology of accessory phases. SIMS analyses of zircon from several of the IOA ores reveal at least two periods of growth after LMG magmatism, at 1039 +/- 4.4 Ma and 1016 +/- 7 Ma to 1000 +/- 9 Ma. In situ EMPA and LA-ICPMS trace element analyses of the zircon rims and cores reveal that in two samples the zircon rims are enriched in rare earth elements (REE) compared to their cores, potentially pointing to a hydrothermal origin. Apatite has unusually high REE and Y concentrations (some total REE2O3 > 20 wt. % oxide and up to 8 wt. % oxide Y2O3), as does titanite, which allowed for the in situ analysis of Sm-Nd in apatite and titanite by LA-MC-ICP-MS. Initial Nd isotopic composition of both ore and host rock apatite and host rock titanite are consistent with published Adirondack initial Nd whole rock data, suggesting a local source for REE in these ores. EMPA and LA-ICPMS trace-element analyses of the major rock-forming minerals indicate that the feldspar have undergone Na-metasomatism and are depleted in REEs

  15. Reactions that modify chemistry in lakes of the national surface water survey

    SciTech Connect

    Lee, S.; Schnoor, J.L.

    1988-01-01

    A simple mass balance equation was used to determine the important reactions that occur in selected lake watersheds of the Adirondack Park, the Southern Blue Ridge Province of the Appalachian Mountains, and a portion of northern Flordia. The mass balance requires only three input parameters: precipitation ion concentration, lake ion concentration, and an evapoconcentration factor appliable to the watershed. It was determined that the most important alkalizing reaction in all three study areas was the production of base cations (Ca2+, Mg2+, and Na1+) by ion exchange and chemical weathering, followed by sulfate adsorption in the Southern Blue Ridge watersheds and nitrate assimilation/reduction in the Adirondack Park.

  16. TROPHIC DYNAMICS OF STRIPED BASS IN SMITH MOUNTAIN LAKE, VIRGINIA

    EPA Science Inventory

    We examined the adequacy of the forage base to meet demand of striped bass in Smith Mountain Lake, Virginia. In regards to prey supply, mean alewife biomass from 1993-1998 was 37 kg/ha and mean gizzard shad biomass from 1990-1997 was 112 kg/ha. Mean annual alewife surplus produ...

  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. Use of stream chemistry for monitoring acidic deposition effects in the Adirondack region of New York

    USGS Publications Warehouse

    Lawrence, G.B.; Momen, B.; Roy, K.M.

    2004-01-01

    Acid-neutralizing capacity (ANC) and pH were measured weekly from October 1991 through September 2001 in three streams in the western Adirondack Mountain region of New York to identify trends in stream chemistry that might be related to changes in acidic deposition. A decreasing trend in atmospheric deposition of SO42- was observed within the region over the 10-yr period, although most of the decrease occurred between 1991 and 1995. Both ANC and pH were inversely related to flow in all streams; therefore, a trend analysis was conducted on (i) the measured values of ANC and pH and (ii) the residuals of the concentration-discharge relations. In Buck Creek, ANC increased significantly (p 0.10). In Bald Mountain Brook, ANC and residuals of ANC increased significantly (p < 0.01), although the trend was diatonic-a distinct decrease from 1991 to 1996 was followed by a distinct increase from 1996 to 2001. In Fly Pond outlet, ANC and residuals of ANC increased over the study period (p < 0.01), although the trend of the residuals resulted largely from an abrupt increase in 1997. In general, the trends observed in the three streams are similar to results presented for Adirondack lakes in a previous study, and are consistent with the declining trend in atmospheric deposition for this region, although the observed trends in ANC and pH in streams could not be directly attributed to the trends in acidic deposition.

  19. Solar and atmospheric forcing on mountain lakes.

    PubMed

    Luoto, Tomi P; Nevalainen, Liisa

    2016-10-01

    We investigated the influence of long-term external forcing on aquatic communities in Alpine lakes. Fossil microcrustacean (Cladocera) and macrobenthos (Chironomidae) community variability in four Austrian high-altitude lakes, determined as ultra-sensitive to climate change, were compared against records of air temperature, North Atlantic Oscillation (NAO) and solar forcing over the past ~400years. Summer temperature variability affected both aquatic invertebrate groups in all study sites. The influence of NAO and solar forcing on aquatic invertebrates was also significant in the lakes except in the less transparent lake known to have remained uniformly cold during the past centuries due to summertime snowmelt input. The results suggest that external forcing plays an important role in these pristine ecosystems through their impacts on limnology of the lakes. Not only does the air temperature variability influence the communities but also larger-scale external factors related to atmospheric circulation patterns and solar activity cause long-term changes in high-altitude aquatic ecosystems, through their connections to hydroclimatic conditions and light environment. These findings are important in the assessment of climate change impacts on aquatic ecosystems and in greater understanding of the consequences of external forcing on lake ontogeny.

  20. Solar and atmospheric forcing on mountain lakes.

    PubMed

    Luoto, Tomi P; Nevalainen, Liisa

    2016-10-01

    We investigated the influence of long-term external forcing on aquatic communities in Alpine lakes. Fossil microcrustacean (Cladocera) and macrobenthos (Chironomidae) community variability in four Austrian high-altitude lakes, determined as ultra-sensitive to climate change, were compared against records of air temperature, North Atlantic Oscillation (NAO) and solar forcing over the past ~400years. Summer temperature variability affected both aquatic invertebrate groups in all study sites. The influence of NAO and solar forcing on aquatic invertebrates was also significant in the lakes except in the less transparent lake known to have remained uniformly cold during the past centuries due to summertime snowmelt input. The results suggest that external forcing plays an important role in these pristine ecosystems through their impacts on limnology of the lakes. Not only does the air temperature variability influence the communities but also larger-scale external factors related to atmospheric circulation patterns and solar activity cause long-term changes in high-altitude aquatic ecosystems, through their connections to hydroclimatic conditions and light environment. These findings are important in the assessment of climate change impacts on aquatic ecosystems and in greater understanding of the consequences of external forcing on lake ontogeny. PMID:27220094

  1. Regional assessment of the response of the acid-base status of lake watersheds in the Adirondack region of New York to changes in atmospheric deposition using PnET-BGC.

    PubMed

    Chen, Limin; Driscoll, Charles T

    2005-02-01

    Understanding the response of soil and surface waters to changes in atmospheric deposition is critical for guiding future legislation on air pollution. The Adirondack region of New York experiences among the most severe ecological impacts from acidic deposition. The region is characterized by considerable variability in atmospheric deposition, surficial and bedrock geology, hydrologic flow paths, and vegetation resulting in variability in effects of acidic deposition. In this study, an integrated biogeochemical model (PnET-BGC) was applied to 37 forest lake watersheds to assess the response of soil and surface waters of the Adirondacks to changes in atmospheric deposition at a regional scale. Model-simulated surface water chemistry was validated against data from two synoptic surveys conducted in 1984 and 2001. Results indicate that the model is able to capture the observed changes in surface water chemistry during this period. The model was further used to forecast the response of soil and surface waters to three future emission control scenarios. Results indicate that under the Clean Air Act, surface water SO4(2-) concentrations will continue to decrease at a median rate of -0.38 microeq/L-yr, and surface water ANC is predicted to increase at a median rate of 0.11 microeq/L-yr. More aggressive emission reductions will accelerate the rate of recovery. Under an aggressive control scenario, which represents an additional 75% reduction in SO2 emissions beyond the implementation of the Clean Air Act, surface water SO4(2-) concentrations are predicted to decrease at a median rate of -0.88 microeq/L-yr, and surface water ANC is predicted to increase at a median rate of 0.43 microeq/L-yr. Model predictions of several biologically relevant chemical indicators are also reported.

  2. 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.

  3. Phytoplankton dynamics in three Rocky Mountain Lakes, Colorado, USA

    USGS Publications Warehouse

    McKnight, Diane M.; Smith, R.L.; Bradbury, J.P.; Baron, J.S.; Spaulding, S.

    1990-01-01

    In 1984 and 1985 in Loch Vale, Rocky Mountain National Park, 3 periods were evident: 1) a spring bloom, during snowmelt, of the planktonic diatom Asterionella formosa, 2) a mid-summer period of minimal algal abundance, and 3) a fall bloom of the blue-green alga Oscillatoria limnetica. Seasonal phytoplankton dynamics are controlled partially by the rapid flushing rate during snowmelt and the transport of phytoplankton from the highest lake to the lower lakes by the stream, Icy Brook. During snowmelt, the A. formosa population in the most downstream lake has a net rate of increase of 0.34 d-1. The decline in A. formosa after snowmelt may be related to grazing by developing zooplankton populations. -from Authors

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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. PMID:25764458

  10. 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.

  11. 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...

  12. Use of stream chemistry for monitoring acidic deposition effects in the Adirondack region of New York.

    PubMed

    Lawrence, Gregory B; Momen, Bahram; Roy, Karen M

    2004-01-01

    Acid-neutralizing capacity (ANC) and pH were measured weekly from October 1991 through September 2001 in three streams in the western Adirondack Mountain region of New York to identify trends in stream chemistry that might be related to changes in acidic deposition. A decreasing trend in atmospheric deposition of SO4/2- was observed within the region over the 10-yr period, although most of the decrease occurred between 1991 and 1995. Both ANC and pH were inversely related to flow in all streams; therefore, a trend analysis was conducted on (i) the measured values of ANC and pH and (ii) the residuals of the concentration-discharge relations. In Buck Creek, ANC increased significantly (p < 0.05) over the 10 yr, but the residuals of ANC showed no trend (p > 0.10). In Bald Mountain Brook, ANC and residuals of ANC increased significantly (p < 0.01), although the trend was diatonic-a distinct decrease from 1991 to 1996 was followed by a distinct increase from 1996 to 2001. In Fly Pond outlet, ANC and residuals of ANC increased over the study period (p < 0.01), although the trend of the residuals resulted largely from an abrupt increase in 1997. In general, the trends observed in the three streams are similar to results presented for Adirondack lakes in a previous study, and are consistent with the declining trend in atmospheric deposition for this region, although the observed trends in ANC and pH in streams could not be directly attributed to the trends in acidic deposition.

  13. Use of stream chemistry for monitoring acidic deposition effects in the Adirondack region of New York.

    PubMed

    Lawrence, Gregory B; Momen, Bahram; Roy, Karen M

    2004-01-01

    Acid-neutralizing capacity (ANC) and pH were measured weekly from October 1991 through September 2001 in three streams in the western Adirondack Mountain region of New York to identify trends in stream chemistry that might be related to changes in acidic deposition. A decreasing trend in atmospheric deposition of SO4/2- was observed within the region over the 10-yr period, although most of the decrease occurred between 1991 and 1995. Both ANC and pH were inversely related to flow in all streams; therefore, a trend analysis was conducted on (i) the measured values of ANC and pH and (ii) the residuals of the concentration-discharge relations. In Buck Creek, ANC increased significantly (p < 0.05) over the 10 yr, but the residuals of ANC showed no trend (p > 0.10). In Bald Mountain Brook, ANC and residuals of ANC increased significantly (p < 0.01), although the trend was diatonic-a distinct decrease from 1991 to 1996 was followed by a distinct increase from 1996 to 2001. In Fly Pond outlet, ANC and residuals of ANC increased over the study period (p < 0.01), although the trend of the residuals resulted largely from an abrupt increase in 1997. In general, the trends observed in the three streams are similar to results presented for Adirondack lakes in a previous study, and are consistent with the declining trend in atmospheric deposition for this region, although the observed trends in ANC and pH in streams could not be directly attributed to the trends in acidic deposition. PMID:15224937

  14. 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.

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

    PubMed

    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

  16. 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

  17. 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.

  18. 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.

  19. 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

  20. Granite emplacement during tectonic exhumation: The Adirondack example

    NASA Astrophysics Data System (ADS)

    Selleck, Bruce W.; McLelland, James M.; Bickford, M. E.

    2005-10-01

    Sensitive high-resolution ion microprobe U-Pb zircon ages for late to posttectonic leucogranites fix the timing of extensional collapse of a portion of the Mesoproterozoic Grenville orogen of eastern North America. Plutons of Lyon Mountain Granite (LMG) were emplaced within the Carthage Colton shear zone synchronously with formation of extensional mylonite at 1045 1037 Ma. Leucogranite melts were generated in the hot granulite facies core of the Adirondack Highlands Central Granulite terrane that served as the lower plate for down-to-the-northwest extension. The LMG suite is associated with high-temperature hydrothermal magnetite deposits in the Adirondack Highlands, and widespread Cl + CO2 hydrothermal alteration of upper-plate rocks is localized along the Carthage Colton shear zone where LMG granites are present. The relationships between melt generation, granite intrusion, high strain rates, extensional collapse, and high- temperature hydrothermal activity provide a framework for understanding midcrustal processes in modern and ancient orogenic belts.

  1. 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. PMID:19544737

  2. 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.

  3. 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.

  4. 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.

  5. 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).

  6. 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.

  7. 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.

  8. 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. PMID:27029537

  9. Spatiotemporal patterns of high-mountain lakes and related hazards in western Austria

    NASA Astrophysics Data System (ADS)

    Emmer, Adam; Merkl, Sarah; Mergili, Martin

    2015-10-01

    Climate-induced environmental changes are triggering the dynamic evolution of high-mountain lakes worldwide, a phenomenon that has to be monitored in terms of lake outburst hazards. We analyzed the spatial distribution and recent temporal development of high-mountain lakes in a study area of 6139 km2, covering the central European Alps over most of the province of Tyrol and part of the province of Salzburg in western Austria. We identified 1024 natural lakes. While eight lakes are ice-dammed, one-third of all lakes are located in the immediate vicinity of recent glacier tongues, half of them impounded by moraines, half by bedrock. Two-thirds of all lakes are apparently related to LIA or earlier glaciations. One landslide-dammed lake was identified in the study area. The evolution of nine selected (pro)glacial lakes was analyzed in detail, using multitemporal remotely sensed images and field reconnaissance. Considerable glacier retreat led to significant lake growth at four localities, two lakes experienced stagnant or slightly negative areal trends, one lake experienced a more significant negative areal trend, and two lakes drained completely during the investigation period. We further (i) analyzed the susceptibility of selected lakes to glacial lake outburst floods (GLOFs), using two different methods; (ii) identified potential triggers and mechanisms of GLOFs; (iii) calculated possible flood magnitudes for predefined flood scenarios for a subset of the lakes; and (iv) delineated potentially impacted areas. We distinguished three phases of development of bedrock-dammed lakes: (a) a proglacial, (b) a glacier-detached, and (c) a nonglacial phase. The dynamics - and also the susceptibility of a lake to GLOFs - decrease substantially from (a) to (c). Lakes in the stages (a) and (b) are less prominent in our study area, compared to other glacierized high-mountain regions, leading us to the conclusion that (i) the current threat to the population by GLOFs is lower but

  10. Physical Controls on Delta Formation and Carbon Storage in Mountain Lakes

    NASA Astrophysics Data System (ADS)

    Scott, D.; Wohl, E.

    2014-12-01

    Carbon acts as a component in greenhouse gases that regulate global climate. It is imperative to understand the transport and storage of carbon in order to understand and manage climate change. We examine terrestrial carbon storage in mountain lake deltas as a way of furthering our understanding of the terrestrial carbon sink, which is a poorly understood but significant contributor to the global carbon cycle. We examined subalpine lake deltas in the Washington Cascade Range and Colorado Front Range to test the following hypotheses: 1) The size of the deltaic carbon sink is strongly correlated with incision at the outlet of the lake and the topography of the basin. 2) Areas of high exhumation rates will have smaller and fewer deltas because a high exhumation rate should lead to more confined basins and more colluvium available to dam lake outlets, preventing lake level drop and corresponding delta formation. 3) High-energy deltas will transport more carbon to lakes, avoiding the deltaic carbon sink. At 27 lakes, we surveyed mountain lake deltas and took sediment samples, surveyed lake outlets in the field, and measured lake valley confinement in GIS to test hypotheses 1 and 3. Across the Snoqualmie and Skykomish watersheds in the Washington Cascades and the Colorado Front Range, we took a census of the number of natural lakes and the proportion of those lakes with deltas to test hypothesis 2. Preliminary results indicate that the Washington Cascades (high exhumation rate) have a higher density of lakes, but fewer deltas, than the Colorado Front Range (low exhumation rate). We also suspect that deltas in the Washington Cascades will have a lower carbon content than the Colorado Front Range due to generally higher energy levels on deltas. Finally, we found a substantial difference in the geomorphology and sediment type between beaver-affected and non-beaver-affected lakes in the Colorado Front Range.

  11. 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.

  12. 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

  13. 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

  14. 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

  15. 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.

  16. Contrasted evolution of glacial lakes along the Hindu Kush Himalaya mountain range between 1990 and 2009

    NASA Astrophysics Data System (ADS)

    Gardelle, Julie; Arnaud, Yves; Berthier, Etienne

    2011-01-01

    In this study, we present a first regional assessment of glacial lake distribution and evolution in the Hindu Kush Himalaya (HKH). Seven sites have been selected between Bhutan and Afghanistan, to capture the climatic variability along the 2000-km long mountain range. For each site, glacial lakes have been mapped with LANDSAT satellite imagery acquired in 1990, 2000 and 2009, using an automatic classification. In the East (India, Nepal and Bhutan), glacial lakes are bigger and more numerous than in the West (Pakistan, Afghanistan), and have grown continuously between 1990 and 2009 by 20% to 65%. On the other hand, during the same period, the glacial lake coverage has shrunk in the Hindu Kush (-50%) and the Karakorum (-30%). This east/west pattern of lake changes seems in agreement with sparse glaciological measurements that suggest less (or even no) ice loss in the western part of the HKH.

  17. 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...

  18. 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.

  19. High-mountain lakes as a hotspot of dissolved organic matter production in a changing climate

    NASA Astrophysics Data System (ADS)

    Abood, P. H.; Williams, M. W.; McKnight, D. M.; Hood, E. H.

    2004-12-01

    Changes in climate may adversely affect mountain environments before downstream ecosystems are affected. Steep topography, thin soils with limited extent, sparse vegetation, short growing seasons, and climatic extremes (heavy snowfalls, cold temperatures, high winds), all contribute to the sensitivity of high mountain environments to perturbations. Here we evaluate the role of oligatrophic high-elevation lakes as "hot spots" of aquatic production that may respond to changes in temperature, precipitation amount, and pollution deposition faster and more directly than co-located terrestrial ecosystems. Our research was conducted in the Rocky Mountains, USA. Water samples were collected for dissolved organic carbon (DOC), other solutes, and water isotopes over the course of the runoff season along a longitudinal transect of North Boulder Creek in the Colorado Front Range from the continental divide and alpine areas to downstream forested systems. Sources of DOC were evaluated using chemical fractionation with XAD-8 resins and fluorescence spectroscopy. There was net DOC production in the two alpine lakes but not for the forested subalpine lake. Oxygen-18 values showed that water residence times in lakes increased dramatically in late summer compared to snowmelt. Chemical fractionation of DOC showed there was a increase in the non-humic acid content across the summer of 2003 at all elevations, with alpine waters showing greater increases than subalpine waters. The fluorescence properties of DOC and water isotopes suggested that DOC in aquatic systems was primarily derived from terrestrial precursor material during snowmelt. However, fluorescence properties of DOC in high-elevation lakes on the recession limb of the hydrograph suggest DOC derived from algal and microbial biomass in the lakes was a more important source of DOC in late summer and fall. Alpine lakes produced 14 times more DOC on unit area basis compared to the surrounding terrestrial ecosystems. We

  20. Assessment of sediments in lakes at the Rocky Mountain Arsenal using the sediment quality triad

    SciTech Connect

    Pearson, M.S.; Clements, W.H.

    1995-12-31

    The authors used the sediment quality triad to assess toxicity of sediments from three lakes located at the Rocky Mountain Arsenal (Superfund site), Denver, CO. The primary contaminants of concern are aldrin, endrin, dieldrin, DDT, DDE, As, and Hg. Preliminary results indicated lower macroinvertebrate density at stations in Lower Derby Lake compared to stations in Ladora and Mary Lakes. Mean diversity, as measured by the Shannon-Weaver Index, at Lower Derby was < 1.0, while Lakes Mary and Ladora were 2.0 and 2.2 respectively. Invertebrate communities were dominated by Chironomidae (Diptera) in all three lakes (> 80%). Chironomus tentans laboratory toxicity tests showed that mortality was highly variable among lakes and stations, and ranged from 0 to 93%. Lake sediment had the greatest toxic effects, as chironomids exposed to six of 10 stations exhibited > 70% mortality. In Lower Derby Lake four of 12 stations had > 50% mortality while no site at Lake Mary showed > 40% mortality. Results of acute toxicity tests with pore water generally agreed with the trends of the sediment toxicity tests. Results of toxicity tests and benthic sampling may have been influenced by differences in sediment characteristics among stations.

  1. 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.

  2. Phosphorus Fluxes in the Beartooth Mountains: a Record of Detailed P Geochemistry from Island Lake

    NASA Astrophysics Data System (ADS)

    McLennan, D. A.; Latimer, J. C.; Williams, T. M.; Brown, S. R.; Stone, J.; McCune, A.

    2014-12-01

    Island Lake, situated within the Precambrian rocks of the Beartooth Mountains that run along the border of Wyoming and Montana, is a glacial lake located at the tree line with an elevation of 3048 m, a maximum water depth of 33 m, a catchment area of 11.7 km2, and a lake area of 0.61 km2. Like many alpine lakes, Island Lake is highly transparent with a deep chlorophyll maximum. Alpine settings may be more susceptible to small perturbations in climate and thus good sensors for investigating climate change. It is hypothesized that this low-nutrient alpine lake has shifted from a nitrogen-limiting system to one that is limited by phosphorus (P) availability. In summer 2013, a 1.54-m sediment core was collected for diatom and geochemical analyses, including P and metals. Detailed P geochemistry can be used to elucidate landscape evolution and P burial fluxes can provide insight into biogeochemical cycling over time. Changes in landscape due to fire, zonal shifts in vegetation, and shifts in climatological factors such as precipitation can impact the bioavailability of P entering the lake as well as burial fluxes. The sediment record will clarify the role of P in lake biogeochemical cycling at Island Lake through the Holocene. Planktonic diatom abundances have been used to reconstruct a history of Holocene lake stratification, and ongoing detailed P geochemistry using a sequential extraction technique (SEDEX) will be used to identify the role of P fluxes on productivity within the lake. SEDEX can differentiate between P associated with oxides/oxyhydroxides, mineral fractions, and organic matter, and the relative changes in these fractions provide insight into landscape dynamics. Coupled with diatom proxies, P geochemistry can also provide a better understanding of biogeochemical cycling within the lake. This multiproxy approach should provide insight into the responses within the catchment to environmental changes over the Holocene.

  3. Using mark-recapture methods to estimate fish abundance in small mountain lakes

    USGS Publications Warehouse

    Gresswell, Robert E.; Liss, W.J.; Lomnicky, G.A.; Deimling, E.; Hoffman, Robert L.; Tyler, T.

    1997-01-01

    The majority of lacustrine fish populations in the western USA are located far from the nearest road. Although mark-recapture techniques are widely accepted for estimating population abundance, these techniques have been broadly ignored for fisheries surveys in remote mountain lakes because of restricted access and associated logistical constraints. In this study, mark recapture experiments were used to estimate fish population abundance in nine small (< 7 ha) lakes of the North Cascades National Park Service Complex. Fish in the mark sample were collected by angling, fin-clipped, and immediately released; fish were recaptured with variable mesh monofilament gill nets. A single-census Petersen estimator was used to calculate abundance in each lake, and assumptions for unbiased estimates appeared to be satisfied in most cases. Post-release mortality of angler-captured fish was low. The small size of these lakes in conjunction with the brief period of rime allotted for each individual experiment apparently reduced the probability of unequal vulnerability and mortality for marked and unmarked fish. Single-census mark-recapture experiments appeared to provide reasonable estimates of population abundance in these mountain lakes. Resulting estimates furnish a substantial increase in information when compared to more ubiquitous assessments of relative abundance, but the logistical requirements are modest. We believe that this technique may useful for survey purposes in other small, remote lakes.

  4. Factors affecting acid neutralizing capacity in the Adirondack region of New York: a solute mass balance approach.

    PubMed

    Ito, Mari; Mitchell, Myron J; Driscoll, Charles T; Roy, Karen M

    2005-06-01

    High rates of acidic deposition in the Adirondack region of New York have accelerated acidification of soils and surface waters. Annual input-output budgets for major solutes and acid-neutralizing capacity (ANC) were estimated for 43 drainage lake-watersheds in the Adirondacks from 1998 to 2000. Sulfate was the predominant anion on an equivalent basis in both precipitation and drainage export. Calcium ion had the largest cation drainage export, followed by Mg2+. While these watersheds showed net nitrogen (N) retention, the drainage losses of SO4(2-), Cl-, base cations, and ANC exceeded their respective inputs from precipitation. Land cover (forest type and wetlands) affected the export of SO4(2-), N solutes, and dissolved organic carbon (DOC). The relationships of solute export with elevation (negative for base cations and Cl-, positive for NO3- and H+) suggest the importance of the concomitant changes of biotic and abiotic watershed characteristics associated with elevational gradients. The surface water ANC increased with the sum of base cations and was greatest in the lakes with watersheds characterized by thick deposits of glacial till. The surface water ANC was also higher in the lake-watersheds with lower DOC export. Some variation in lake ANC was associated with variability in acidic deposition. Using a classification system previously developed for Adirondack lakes on the basis primarily of surficial geology, lake-watersheds were grouped into five classes. The calculated ANC fluxes based on the major sinks and sources of ANC were comparable with measured ANC for the thick-till (I) and the medium-till lake-watersheds with low DOC (II). The calculated ANC was overestimated for the medium-till with high DOC (III) and the thin-till with high DOC (V) lake-watersheds, suggesting the importance of naturally occurring organic acids as an ANC sink, which was not included in the calculations. The lower calculated estimates than the measured ANC for the thin-till lake

  5. Influence of natural acidity and fisheries management activities upon the status of Adirondack fish populations

    SciTech Connect

    Retzsch, W.C.; Everett, A.G.

    1981-01-01

    Acidification and the disappearance of fish from some Adirondack waters does not appear to be caused solely by acid rain. Acidification is a natural process under certain conditions and precipitation acidified by industrial emissions appears to be only one of many possible causes of pond, lake and stream acidification. Factors other than acid precipitation can cause acidification or reduce fish stocks. As a result of glaciation, northern New York State has hundreds of glacial ponds and lakes, most of which are dystrophic or oligotrophic. Many such waters are located in the western and central portions of the Adirondacks, an area frequently cited as exhibiting the most pronounced effects of acid rain. It is widely recognized that natural unpolluted bogs and peat deposits result in low pH environments. Seasonal and weather conditions also appear to have a substantial effect upon the acidity of peat-bog outflows. An evaluation of recent survey data on critically acidified Adirondack waters indicates that of 192 waters with values less than pH 5.0, approximately 61 percent appear to be directly influenced by natural bog conditions and an additional 14 percent are probably influenced. A review of historical and recent survey data suggest that significant factors, such as natural causes of acidification, low oxygen concentrations, high CO/sub 2/ and H/sub 2/S concentrations, and extreme temperatures may have been ignored or underestimated in evaluating the cause of acidification and fish disappearances in some Adirondack waters. Another factor responsible for the current status of fish stocks in the Adirondacks involves past and present fishery resource management activities.

  6. 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.

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. 76 FR 72444 - Notice of Lodging of Consent Decree Resolving Claims for Contamination of Mountain Lake in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-23

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Notice of Lodging of Consent Decree Resolving Claims for Contamination of Mountain Lake in the Presidio of... contamination, to pay $4 million for repair or replacement of the overflow pipeline that drains Mountain...

  13. 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.

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. 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

  19. Nitrate deposition and impact on Adirondack streams

    SciTech Connect

    Simonin, H.A.; Kretser, W.A.

    1997-12-31

    Acidic deposition has a great impact on water chemistry and fish populations in the Adirondack region. Although the Clean Air Act Amendments of 1990 have resulted in some reductions of sulfate deposition, nitrate deposition has not yet been well controlled, and continues to impact aquatic resources. As part of the USEPA funded Episodic Response Project four Adirondack headwater streams were intensively monitored over an 18 month period. Atmospheric deposition was also monitored at a centrally located station. The quantity of nitrate being deposited on the study watersheds was calculated based on monthly net deposition data which ranged from 0.6 kg/ha/month to 3.6 kg/ha/month. These data were then compared to the monthly export of nitrate from the watershed in these streams. Nitrate concentrations were highest in the streamwater during the spring snowmelt period prior to the time when forest vegetation actively utilizes nitrate. On an annual basis the amount of nitrate which left the watershed via stream water exceeded the amount which fell as nitrate deposition. These data are important in documenting the impact of nitrate in the acidification of Adirondack streams during the spring, which coincides with brook trout hatching. Control programs for nitrous oxide emissions are presently aimed at reducing ozone levels during the May-September period. These emissions control programs need to be expanded to also reduce nitrate deposition in the sensitive Adirondack region during the winter and spring periods when nitrate deposition has its greatest impact on aquatic resources.

  20. 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.

  1. Abundances, Identity, and Growth State of Actinobacteria in Mountain Lakes of Different UV Transparency

    PubMed Central

    Warnecke, Falk; Sommaruga, Ruben; Sekar, Raju; Hofer, Julia S.; Pernthaler, Jakob

    2005-01-01

    The occurrence, identity, and activity of microbes from the class Actinobacteria was studied in the surface waters of 10 oligo- to mesotrophic mountain lakes located between 913 m and 2,799 m above sea level. Oligonucleotide probes were designed to distinguish between individual lineages within this group by means of fluorescence in situ hybridization (FISH). Bacteria of a single phylogenetic lineage (acI) represented >90% of all Actinobacteria in the studied lakes, and they constituted up to 70% of the total bacterial abundances. In the subset of eight lakes situated above the treeline, the community contribution of bacteria from the acI lineage was significantly correlated with the ambient levels of solar UV radiation (UV transparency, r2 = 0.72; P < 0.01). Three distinct genotypic subpopulations were distinguished within acI that constituted varying fractions of all Actinobacteria in the different lakes. The abundance of growing actinobacterial cells was estimated by FISH and immunocytochemical detection of bromodeoxyuridine (BrdU) incorporation into de novo-synthesized DNA. The percentages of Actinobacteria with visible DNA synthesis approximately corresponded to the average percentages of BrdU-positive cells in the total assemblages. Actinobacteria from different subclades of the acI lineage, therefore, constituted an important autochthonous element of the aquatic microbial communities in many of the studied lakes, potentially also due to their higher UV resistance. PMID:16151148

  2. 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.

  3. 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. PMID:24973278

  4. 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

  5. Perspective View, Syracuse, Oneida Lake, Utica, Upstate New York

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This perspective view of upstate New York shows Lake Ontario in the lower left, the Adirondack Mountains in the upper left, and the Catskill Mountains on the right. This image was generated using topographic data from SRTM and an enhanced true-color Landsat 5 satellite image. Topographic shading in the image was enhanced with false shading derived from the elevation model. Topographic expression is exaggerated 6X.

    Fall foliage appears in a variety of colors, as expected for the mid-October Landsat data used here. Redder vegetation generally occurs at higher elevations and toward the north (left), especially in the Adirondack Mountains. The back edge of the data set forms a false skyline. Oneida Lake is just below the scene center. From the lake, Syracuse is toward the lower right, Rome is toward the upper left, and Utica is directly upward from the lake. Oswego is on the shore of Lake Ontario at the bottom edge of the image. All four cities appear whitish. The other whitish areas toward the north (left) are thin clouds in the satellite image. At Herkimer, just beyond Utica, the Mohawk River exits the Adirondacks and flows eastward into rugged terrain and onward toward Albany. Upon close inspection at full resolution, one can see the Erie Canal (dark blue line) running east from Oneida Lake to connect to the Mohawk River. Other parts of the canal connect to the Oswego River running north (left) to Lake Ontario, to Onandaga Lake next to Syracuse, and Cayuga Lake in the lower right corner of the image (just the edge of the lake). Parts of Owasco, Skaneateles, and Otisco Lakes are visible in the lower right (bottom to top). These are some of the Finger Lakes of central New York, with their narrow valleys (Otisco Lake is almost completely hidden by its valley walls). At the full image resolution, a thin white line marks the New York State Thruway from the bottom to the top of the image, passing north (left) of the Onandaga Lake next to Syracuse and through Utica

  6. Chemistry of lakes in designated wilderness areas in the western United States.

    PubMed

    Eilers, J M; Brakke, D F; Landers, D H; Overton, W S

    1989-04-01

    A synoptic survey of 719 lakes representing an estimated 10,393 lakes in mountainous areas of the western United States was conducted in autumn 1985. Nearly two-thirds of the study lakes were located in wilderness areas or national parks and were sampled by ground access. The results of a comparability study of 45 wilderness lakes accessed by helicopter and ground crews indicated that the data were generally indistinguishable, making it possible to use data from lakes sampled by ground crews without modification. Wilderness lakes had lower acid neutralizing capacity (ANC), base cations, sulfate, and dissolved organic carbon than nonwilderness lakes throughout the West. The highest estimated number (849) and percentage (42.1) of low ANC (≤50 μeq L(-1)) wilderness lakes were located in California; the lowest number (66) was located in the Southern Rockies. The Sierra Nevada contained an estimated 808 low ANC lakes, representing the largest subpopulation of low ANC lakes associated with an individual mountain range in the West. Wilderness lakes in selected geographic areas of the Rocky Mountains generally contained higher concentrations of major ions than lakes in the far West and the concentrations generally increased from the Northern to the Southern Rockies. Comparison of wilderness lakes in the West with lakes in the Adirondack Park, New York, and the Boundary Waters Canoe Area/Voyagers National Park in Northeastern Minnesota showed that western lakes are highly sensitive resources that currently exhibit little evidence of anthropogenic acidification. Although wilderness lakes do not exhibit symptoms of chronic acidification, short-term depression of pH and ANC from snowmelt and thunderstorms occur and episodic acidification influenced by anthropogenic sources cannot be discounted on the basis of this survey.

  7. 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

  8. 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.

  9. Biogenic phosphorus in oligotrophic mountain lake sediments: differences in composition measured with NMR spectroscopy.

    PubMed

    Ahlgren, Joakim; Reitzel, Kasper; Danielsson, Rolf; Gogoll, Adolf; Rydin, Emil

    2006-12-01

    Phosphorus (P) composition in alkaline sediment extracts from three Swedish oligotrophic mountain lakes was investigated using 31P-NMR spectroscopy. Surface sediments from one natural lake and two mature reservoirs, one of which has received nutrient additions over the last 3 years, were compared with respect to biogenic P composition. The results show significant differences in the occurrence of labile and biogenic P species in the sediments of the different systems. The P compound groups that varied most between these three systems were pyrophosphate and polyphosphates, compound groups known to play an important role in sediment P recycling. The content of these compound groups was lowest in the reservoirs and may indicate a coupling between anthropogenic disturbances (i.e., impoundment) to a water system and the availability of labile P species in the sediment. A statistical study was also conducted to determine the accuracy and reliability of using 31P-NMR spectroscopy for quantification of sediment P forms. PMID:17070896

  10. 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.

  11. [Spatiotemporal characteristics of nitrogen and phosphorus in a mountainous urban lake].

    PubMed

    Bao, Jing-Yue; Bao, Jian-Guo; Li, Li-Qing

    2014-10-01

    Longjing Lake in Chongqing Expo Garden is a typical representative of mountainous urban lake. Based on water quality monitoring of Longjing Lake, spatiotemporal characteristics of nitrogen and phosphorus and their relations were analyzed, combined with natural and human factors considered. The results indicated that annual average concentrations of TN and TP in overall lake were (1.42 ± 0.46) mg · L(-1) and (0.09 ± 0.03) mg · L(-1), nitrogen and phosphorus concentrations fluctuated seasonally which were lower during the flooding season than those during the dry season. Nitrogen and phosphorus concentration in main water area, open water areas and bay areas of Longjing Lake were distributed with temporal and spatial heterogeneity by different regional influencing factors. The seasonal variation of the main water area was basically consistent with overall lake. Two open water areas respectively connected the main water area with the upstream region, bay areas. TN and TP concentrations were gradually reduced along the flow direction. Upstream water quality and surrounding park functional layout impacted nitrogen and phosphorus nutrient concentrations of open water areas. Nutrient concentrations of typical bay areas were higher than those of main water area and open water areas. The mean mass fraction of PN/TN and PP/TP accounted for a large proportion (51.7% and 72.8%) during the flooding season, while NO(3-)-N/TN and SRP/TP accounted for more (42.0% and 59.4%) during the dry season. The mass fraction of ammonia nitrogen and dissolved organic nitrogen in total nitrogen were relatively stable. The annual mean of N/P ratio was 18.429 ± 7.883; the period of nitrogen limitation was 5.3% while was 21.2% for phosphorus limitation.

  12. Differential utilization patterns of dissolved organic phosphorus compounds by heterotrophic bacteria in two mountain lakes

    PubMed Central

    Rofner, Carina; Sommaruga, Ruben; Pérez, María Teresa

    2016-01-01

    Although phosphorus limitation is common in freshwaters and bacteria are known to use dissolved organic phosphorus (DOP), little is known about how efficiently DOP compounds are taken up by individual bacterial taxa. Here, we assessed bacterial uptake of three model DOP substrates in two mountain lakes and examined whether DOP uptake followed concentration-dependent patterns. We determined bulk uptake rates by the bacterioplankton and examined bacterial taxon-specific substrate uptake patterns using microautoradiography combined with catalyzed reporter deposition–fluorescence in situ hybridization. Our results show that in the oligotrophic alpine lake, bacteria took up ATP, glucose-6-phosphate and glycerol-3-phosphate to similar extents (mean 29.7 ± 4.3% Bacteria), whereas in the subalpine mesotrophic lake, ca. 40% of bacteria took up glucose-6-phosphate, but only ∼20% took up ATP or glycerol-3-phosphate. In both lakes, the R-BT cluster of Betaproteobacteria (lineage of genus Limnohabitans) was over-represented in glucose-6-phosphate and glycerol-3-phosphate uptake, whereas AcI Actinobacteria were under-represented in the uptake of those substrates. Alphaproteobacteria and Bacteroidetes contributed to DOP uptake proportionally to their in situ abundance. Our results demonstrate that R-BT Betaproteobacteria are the most active bacteria in DOP acquisition, whereas the abundant AcI Actinobacteria may either lack high affinity DOP uptake systems or have reduced phosphorus requirements. PMID:27312963

  13. Genetic diversity of planktonic eukaryotes in high mountain lakes (Central Pyrenees, Spain).

    PubMed

    Triadó-Margarit, Xavier; Casamayor, Emilio O

    2012-09-01

    The genetic diversity of planktonic eukaryotic microorganisms (size range 3-40 µm) inhabiting 11 alpine lakes of the Central Pyrenees (Spain) was analysed by cloning and sequencing of the 18S rRNA gene. The selected lakes covered a wide range of environmental conditions representative of the regional landscape heterogeneity. Overall, we obtained 953 sequences (averaged length 750 bp) that were grouped in 343 representative OTUs (98% identity). The genetic richness was high, and the 18S rRNA gene sequences spread within nine high-rank taxonomic groups and grouped in 26 eukaryal classes. Most of the sequences affiliated with Stramenopiles (> 55% of total sequences, mostly Chrysophyceae), Cryptophyta and Alveolata (15% each). Three groups had relative abundance < 5%, i.e. Opisthokonta (mostly Fungi), Viridiplantae (mostly Chlorophyceae) and Rhizaria (cercomonads). Finally, minor groups were related to Katablepharidophyta, Euglenozoa and Telonemida. The lakes showed a different community structure being pH, and phosphorous and Chl a concentrations the main environmental drivers. The novelty level was high, and a quarter of the retrieved OTUs were notably divergent (< 97% identity) from any previously known sequence, mainly for Rhizaria and Opisthokonta. More than 50% of the sequences affiliated with clusters exclusively formed by uncultured protists. Cryptophyta and Viridiplantae showed the largest number of sequences closely related to cultured counterparts. This work is the first description of the genetic diversity of eukaryotic assemblages in ultraoligotrophic high mountain lakes, and the study unveils alpine environments as an important reservoir of microbial eukaryotic biodiversity.

  14. Differential utilization patterns of dissolved organic phosphorus compounds by heterotrophic bacteria in two mountain lakes.

    PubMed

    Rofner, Carina; Sommaruga, Ruben; Pérez, María Teresa

    2016-09-01

    Although phosphorus limitation is common in freshwaters and bacteria are known to use dissolved organic phosphorus (DOP), little is known about how efficiently DOP compounds are taken up by individual bacterial taxa. Here, we assessed bacterial uptake of three model DOP substrates in two mountain lakes and examined whether DOP uptake followed concentration-dependent patterns. We determined bulk uptake rates by the bacterioplankton and examined bacterial taxon-specific substrate uptake patterns using microautoradiography combined with catalyzed reporter deposition-fluorescence in situ hybridization. Our results show that in the oligotrophic alpine lake, bacteria took up ATP, glucose-6-phosphate and glycerol-3-phosphate to similar extents (mean 29.7 ± 4.3% Bacteria), whereas in the subalpine mesotrophic lake, ca. 40% of bacteria took up glucose-6-phosphate, but only ∼20% took up ATP or glycerol-3-phosphate. In both lakes, the R-BT cluster of Betaproteobacteria (lineage of genus Limnohabitans) was over-represented in glucose-6-phosphate and glycerol-3-phosphate uptake, whereas AcI Actinobacteria were under-represented in the uptake of those substrates. Alphaproteobacteria and Bacteroidetes contributed to DOP uptake proportionally to their in situ abundance. Our results demonstrate that R-BT Betaproteobacteria are the most active bacteria in DOP acquisition, whereas the abundant AcI Actinobacteria may either lack high affinity DOP uptake systems or have reduced phosphorus requirements. PMID:27312963

  15. 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.

  16. Adirondack Post-Drill (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 to drill into the rock. Debris from the use of the tool is visible to the left of the hole.

  17. 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 (

  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. 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.

  20. 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.

  1. [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.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. Dissolved Organic Matter Characteristics Control Filtered Total Mercury Concentrations in an Adirondack River Basin

    NASA Astrophysics Data System (ADS)

    Burns, D. A.; Aiken, G.; Bradley, P. M.; Journey, C.

    2011-12-01

    Dissolved organic carbon (DOC) plays important roles in the transport and biogeochemical processes that affect mercury (Hg) cycling in the environment. Previous investigations have shown strong correlations between DOC and Hg concentrations in surface waters. Commonly, other DOC-related measures such as ultraviolet absorbance (UV254), and hydrophobic acid content (HPOA) show even stronger positive correlations with Hg in waters indicating the importance of the more aromatic fraction of DOC in Hg cycling. Finally, in-situ optical sensor-derived DOC concentrations have proven useful as inexpensive proxies for estimating Hg concentrations in some surface waters. Here, we describe results from the 493 km2 Upper Hudson River basin in the Adirondack Mountains of New York in which stream water samples were collected for filtered total Hg (FTHg) concentrations, DOC concentrations, UV254, HPOA, and specific ultraviolet absorbance (SUVA, derived from the absorbance and DOC measurements) at two temporal and spatial scales during 2006-09: (1) biweekly to monthly in a 66 km2 basin, and (2) seasonally at 27 synoptic sites distributed across the larger Upper Hudson basin. These results indicate that SUVA values are more strongly correlated with FTHg concentrations than are those of DOC concentrations, especially during summer. The presence of numerous open water bodies in this basin appears to greatly affect DOC and FTHg concentrations and SUVA values as reflected by data collected upstream and downstream of ponds and lakes. Multivariate regression models developed to examine the landscape factors that control spatial variation in SUVA values among synoptic sites indicate that open water area is inversely correlated with these values, reflecting autochthonous carbon sources in lakes/ponds that are more aliphatic in character than that found in streams. In contrast, metrics such as percent riparian area that reflect the influence of soils with high organic carbon content are

  8. Contrasted evolution of glacial lakes along the Hindu-Kush Himalaya mountain range between 1990 and 2009

    NASA Astrophysics Data System (ADS)

    Gardelle, J.; Yves, A.; Berthier, E.

    2011-12-01

    In this study, we present the first assessment of glacial lake distribution and evolution in the Hindu Kush Himalaya (HKH). Seven sites have been selected between Bhutan and Afghanistan, to capture the climatic variability along the 2000-km long mountain range. For each site, glacial lakes have been mapped with LANDSAT satellite imagery acquired in 1990, 2000 and 2009, using an automatic classification. In the East (India, Nepal and Bhutan) glacial lakes are bigger and more numerous than in the West (Pakistan, Afghanistan), and have grown continuously between 1990 and 2009 by 20% to 65%. Conversely, during the same period, the glacial lake coverage has shrunk in the Hindu Kush (-50%) and the Karakorum (-30%). This east/west pattern of lake changes seems in agreement with sparse glaciological measurements that suggest less (or even no) ice loss in the western part of the HKH.

  9. 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.

  10. 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

  11. Response of Rwenzori (Uganda - DR Congo) Glaciers and Mountain Lake Ecosystems to Climate Change: Past, Present, Future

    NASA Astrophysics Data System (ADS)

    Eggermont, H.; Russell, J.; Verschuren, D.

    2007-12-01

    Ice caps and glaciers in the mountains of tropical Africa are expected to disappear within two decades as a result of human-induced global warming. Loss of permanent ice from Africa's mountains will have profound effects on Afroalpine ecosystems, as well as the hydrology and temperature regime of Africa's unique, alpine cold-water lakes. Consequently, there is an urgent need to document the baseline climatic, environmental, and biological conditions in Africa's mountains against which to evaluate future changes. While climatic, limnological, and ecological monitoring can provide key insights into modern conditions, sediments accumulating on the bottom of alpine glacial lakes chronicle the history of central African climate and environmental dynamics, and can thus produce the historical perspective needed for resource conservation. In this context, over the course of three field expeditions (2005-2007) we surveyed virtually all lakes (19) on the Ugandan side of the Rwenzori Mountains, Uganda-Congo, to evaluate the sensitivity of these high-mountain lake ecosystems to climate change and glacier melting. We installed temperature and humidity loggers to monitor ongoing climate change, calibrated paleolimnological proxy indicators (sediment composition, organic carbon, biomarkers, aquatic biota) in surface sediments in relation to their present local lake environment, and analyzed gravity cores from selected lakes to document the history of recent glacier recession and ecosystem response. Here, we present an overview of the currently available climatic and environmental data sets, with a focus on sediment core data. Through comparison of the sedimentary history of glaciated and non-glaciated lake basins, we show that recent glacier recession started around 1880 AD, broadly coincident in timing with declining East African rainfall as documented by regional lake level datasets. However, our data do not suggest rapid glacial expansion coincident with the initiation of this

  12. 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

  13. 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.

  14. 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.

  15. 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

  16. Sorption of toluene by humic acids derived from lake sediment and mountain soil at different pH.

    PubMed

    Chang Chien, S W; Chen, C Y; Chang, J H; Chen, S H; Wang, M C; Mannepalli, Madhava Rao

    2010-05-15

    Contamination of soil and groundwater with BTEX compounds (benzene, toluene, ethylbenzene, and xylene) depends on the sorption behavior of these compounds by soil organic matter (SOM) and humic acids (HAs). In this study sorption of toluene by HAs extracted from lake sediment and mountain soil was investigated. HA suspensions were adjusted to pH 4.00, 6.00, or 8.00 and made to the concentration of 200 mg L(-1). Each HA suspension or solution was subjected to particle size analysis using high performance particle sizer (HPPS). The particle size of HA from lake sediment was around 1000-1200 nm while that from mountain soil was 220-320 nm at suspension pH 4.00. Kinetic studies showed that sorption of toluene by the two HAs followed pseudo-first-order and mainly pseudo-zero-order kinetics. At suspension pH 4.00, the sorption of toluene by the two HAs was best described by Langmuir and Temkin adsorption isotherm models. Further, sorption of toluene by the lake sediment HA was significantly greater than that by mountain soil HA. It was thus suggested that the lake sediment HA with larger particle size may develop beneficially chemical conformation for sorption of toluene and related compounds in soil and associated environments.

  17. 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

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

    PubMed

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

    2015-07-01

    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

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

    PubMed

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

    2015-07-01

    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

  20. 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

  1. 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.

  2. 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

  3. Temporal Variability of Surface CO2 Emissions at the Horseshoe Lake Tree Kill, Mammoth Mountain, CA

    NASA Astrophysics Data System (ADS)

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

    2006-12-01

    Mammoth Mountain is a dacitic volcano located on the southwestern rim of Long Valley caldera in eastern California. An eleven-month-long seismic swarm occurred beneath Mammoth in 1989 and was followed in 1990 by CO2 emissions around the flanks of the volcano, resulting in the formation of large areas of tree kill associated with high soil CO2 concentrations. Carbon dioxide emissions have persisted at Mammoth to the present day, allowing Mammoth to serve as a natural analogue for short-to-long-term CO2 leakage from geologic carbon storage sites. The Horseshoe Lake tree kill is the largest on the volcano and numerous investigations have been conducted here to quantify CO2 emission rates, determine spatial and temporal variability, and understand effects on the near-surface environment. In particular, continuous monitoring of soil CO2 fluxes (accumulation chamber method) and meteorological parameters at a point location was carried out along with repeat flux measurements along a grid in the tree-kill area in 1998-2000. Results showed large temporal variations in both point CO2 fluxes and total aerial CO2 emission rates driven primarily by fluctuations in wind and atmospheric pressure, rather than deep subsurface processes. We will build on previous studies of CO2 emissions at the Horseshoe Lake tree kill and present results of an investigation of CO2 emissions using the eddy covariance and accumulation chamber methods carried out in September-October, 2006. Spatially and temporally averaged net CO2 fluxes (eddy covariance method) will be used in conjunction with repeat point measurements of soil CO2 fluxes along a grid (accumulation chamber method) to quantify present-day CO2 emission, its temporal variability on half- hour to monthly time scales, and the physical controls on this variability. Implications of CO2 emissions at Mammoth Mountain for geologic carbon storage projects will be discussed. This work was supported in part by the Ernest Lawrence Berkeley

  4. 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.

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

    PubMed

    Lawrence, Gregory B; Roy, Karen M; Baldigo, Barry P; Simonin, Howard A; Capone, Susan B; Sutherland, James W; Nierzwicki-Bauer, Sandra A; Boylen, Charles 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 km(2) 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 (ANC(G)). 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 microeq L(-1), whereas 29% were acidified based on an ANC(G) value < 0 microeq 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 microeq L(-1), whereas 5% were acidified based on ANC(G) value < 0 microeq 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.

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

    PubMed

    Lawrence, Gregory B; Roy, Karen M; Baldigo, Barry P; Simonin, Howard A; Capone, Susan B; Sutherland, James W; Nierzwicki-Bauer, Sandra A; Boylen, Charles 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 km(2) 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 (ANC(G)). 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 microeq L(-1), whereas 29% were acidified based on an ANC(G) value < 0 microeq 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 microeq L(-1), whereas 5% were acidified based on ANC(G) value < 0 microeq 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. PMID:18948480

  9. Pleistocene deglaciation chronology of the Amery Oasis and Radok Lake, northern Prince Charles Mountains, Antarctica

    NASA Astrophysics Data System (ADS)

    Fink, David; McKelvey, Barrie; Hambrey, Michael J.; Fabel, Derek; Brown, Roderick

    2006-03-01

    The East Antarctic Ice Sheet is the largest ice mass on Earth with a capacity to raise global sea level by up to 65 m. As the Lambert Glacier-Amery Ice Shelf drainage system is the largest to reach the coast of Antarctica, quantifying its evolution over the Quaternary is a vital component in developing an understanding of the Antarctic response to future climate change. Here we present a deglaciation chronology based on 10Be and 26Al in situ cosmogenic exposure ages of the northern Prince Charles Mountains, which flank the Lambert Glacier-Amery system, and that records the progressive emergence of McLeod Massif and Radok Lake basin from beneath the Mac.Robertson Land lobe of the East Antarctic Ice Sheet. The exposure ages monotonically decrease with both decreasing altitude and increasing proximity to the Amery Ice Shelf at the Antarctic coast. Exposure ages from the crests of McLeod Massif near the edge the Amery Ice Shelf and from Fisher Massif, 75 km further inland, each at ˜1200 m above sea level, are 2.2 ± 0.3 and 1.9 ± 0.2 Ma, respectively, suggesting their continuous exposure above the ice sheet at least since close to the Plio-Pleistocene boundary. An extensive plateau at ˜800 m altitude on McLeod Massif above Battye Glacier records the massif's increased emergence above the ice sheet surface at about between 880 and 930 ka ago indicating 400 m of ice volume reduction in the mid Pleistocene. Correcting these apparent ages for a reasonable choice in erosion rate would extend this event to ˜1.15 Ma — a period identified from Prydz Bay ODP core-1167 when sedimentation composition alters and rates decrease 10-fold. Exposure ages from boulder-mantled erosional surfaces above and beyond the northern end of Radok Lake at 220 m, range from 28 to 121 ka. Independent of choice of model interpretation to explain this age spread, the most recent major reoccupation of Radok Lake by Battye Glacier ice occurred during the last glacial cycle. Moraine ridges at the

  10. Paleomagnetism and geochemistry of the Geordie Lake and Silver Mountain basalts: Implications for the Midcontinent Rift evolution

    NASA Astrophysics Data System (ADS)

    Kulakov, E.; Smirnov, A. V.; Bornhorst, T. J.; Cundari, R.; Hollings, P. N.

    2012-12-01

    We report the results of paleomagnetic and geochemical investigations of two basaltic lava sequences as a part of our on-going efforts to better understand the evolution of North American Midcontinent Rift (MCR) system. The first sequence of 17 flat-lying lava flows is located north of the rift axis, near Geordie Lake (Ontario, Canada). This sequence overlays the ~1108 Ma gabbros of the Coldwell Complex and is thought to be of a similar age, but no direct contact between the basalts and gabbros has been observed. The other sequence of 13 flows slightly dipping northwest is exposed at Silver Mountain (Baraga County, Upper Michigan), south of the rift axis. The lavas form a ~100 m high glacially polished dome, east of the Keweenawan fault, and are surrounded by glacial deposits. The Silver Mountain basalts have been tentatively interpreted to be a part of the Siemens Creek volcanics, the lowermost formation of the Powder Mill Group. At both locations, we collected six to ten core samples from each lava flow for paleomagnetic analyses. Practically all measured samples have yielded well-defined characteristic remanent magnetizations (ChRM) upon thermal demagnetization. After the correction for structural tilt, the group mean from Silver Mountain flows (D=107.9°, I=-60.4°, α95=2.43°, k=232, N=13) is statistically indistinguishable from the group mean direction of the Geordie Lake basalts (D=109.1°, I=-63.1°, α95=3.81°, k=89, N=17). In addition, both mean directions are statistically similar to the direction reported for the reversely magnetized Lower North Shore Volcanics (LNSV) U-Pb dated at 1107.9±0.8 Ma. The Silver Mountain mean direction is similar to that reported for the Powder Mill basalts dated at 1107.3±1.6 Ma. In addition to paleomagnetic analyses, we conducted geochemical analyses of 17 flows of the Geordie Lake sequence and 7 of the Silver Mountain basalts. Trace element compositions of both sequences are very similar to those reported for the

  11. 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.

  12. 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.

  13. 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

    2015-03-01

    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.

  14. 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

    2015-03-01

    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. PMID:25621941

  15. 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.

  16. Organochlorine compounds in trout from lakes over a 1600 meter elevation gradient in the Canadian Rocky Mountains.

    PubMed

    Demers, Marc J; Kelly, Erin N; Blais, Jules M; Pick, Frances R; St Louis, Vincent L; Schindler, David W

    2007-04-15

    The effect of altitude on the concentration and composition of organochlorine compounds (OC) in troutwas investigated along an elevation gradient of 1600 m in the Canadian Rocky Mountains. The eight lakes sampled were within or adjacent to national parks in sparsely settled parts of Alberta and British Columbia, thus contaminants were assumed to have derived from long-range atmospheric transport. Concentrations of several OCs in trout increased significantly with lake elevation. In general, these increases were most pronounced for the higher K(ow) pesticides (i.e., dieldrin and DDTs), and less pronounced for lower K(ow) pesticides (e.g., HCHs and HCB) and PCBs. Most OC concentrations in trout were inversely correlated with fish growth rate. Growth rate explained more of the variation for some OCs (particularly PCBs) than lake elevation. Differences in trophic position (indicated by delta15N) explained little of the variation in OC concentration in comparison to other factors such as lake elevation and the growth rate and age of trout. Using principal component analysis (PCA), we identified the importance of lake elevation and octanol/water partition coefficient (K(ow)) to the OC composition of trout.

  17. Organochlorine compounds in trout from lakes over a 1600 meter elevation gradient in the Canadian Rocky Mountains.

    PubMed

    Demers, Marc J; Kelly, Erin N; Blais, Jules M; Pick, Frances R; St Louis, Vincent L; Schindler, David W

    2007-04-15

    The effect of altitude on the concentration and composition of organochlorine compounds (OC) in troutwas investigated along an elevation gradient of 1600 m in the Canadian Rocky Mountains. The eight lakes sampled were within or adjacent to national parks in sparsely settled parts of Alberta and British Columbia, thus contaminants were assumed to have derived from long-range atmospheric transport. Concentrations of several OCs in trout increased significantly with lake elevation. In general, these increases were most pronounced for the higher K(ow) pesticides (i.e., dieldrin and DDTs), and less pronounced for lower K(ow) pesticides (e.g., HCHs and HCB) and PCBs. Most OC concentrations in trout were inversely correlated with fish growth rate. Growth rate explained more of the variation for some OCs (particularly PCBs) than lake elevation. Differences in trophic position (indicated by delta15N) explained little of the variation in OC concentration in comparison to other factors such as lake elevation and the growth rate and age of trout. Using principal component analysis (PCA), we identified the importance of lake elevation and octanol/water partition coefficient (K(ow)) to the OC composition of trout. PMID:17533830

  18. 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.

  19. The Grenville Orogenic Cycle (ca. 1350-1000 Ma): an Adirondack perspective

    NASA Astrophysics Data System (ADS)

    McLelland, James; Daly, J. Stephen; McLelland, Jonathan M.

    1996-11-01

    The Adirondack Mountains are characterized by three major events that took place during the interval ca. 1350-1000 Ma. The earliest of these is the arc-related Elzevirian Orogeny (ca. 1350-1185 Ma) during which substantial volumes of juvenile calc-alkaline crust were added to the Adirondacks as well as to the northwest segment of the Central Metasedimentary Belt. Data from the southwestern United States as well as from Ireland and Baltica indicate that Elzevirian magmatism and orogeny were of global dimensions. Within the southwestern sector of the Grenville Province, the Elzevirian Orogeny culminated at ca. 1185 Ma when accretion of all outboard terranes was completed. Compressional orogeny related to this convergence resulted in overthickened crust and lithosphere which subsequently delaminated giving rise to orogen collapse and AMCG magmatism that swept southeastward from the Frontenac Terrane into the Adirondack Highlands during the interval ca. 1180-1130 Ma. Localized compressional events within neighboring parts of the Grenville Province emphasize the continued existence of contraction during this interval, although crustal extension caused local in sedimentary basins in which were deposited the Flinton and the St. Boniface Groups. The Adirondacks have not yet provided any record of events within the interval ca. 1125-1100 Ma, although there is evidence of contraction elsewhere in the southwestern Grenville Province at that time. At 1100-1090 Ma the northern Adirondack Highlands were invaded by mildly A-type hornblende granites (Hawkeye suite) that are interpreted to be the result of local crustal thinning contemporaneous with rifting and mafic magmatism taking place in the Midcontinent rift. Immediately following, at ca. 1090 Ma, the global-scale continental collision of the Ottawan Orogeny was initiated. Strong convergence, deformation, and metamorphism continued to at least ca. 1070 Ma, and rocks older than this are profoundly affected by this event

  20. The Late Holocene Compositionally Zoned Glass Mountain Eruption at Medicine Lake Volcano, California

    NASA Astrophysics Data System (ADS)

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

    2008-12-01

    The spectacular Glass Mountain rhyolite-dacite flow erupted high on the east side of Medicine Lake volcano 950 yrs ago, producing one cubic kilometer of pumice and lava from more than a dozen vents along a 5-km- long fissure. Detailed mapping and chemical/petrographic analysis of 107 lava and tephra samples, 40 quenched andesitic blobs, 18 co-magmatic cumulates, and 6 granitoid fragments show that the eruption commenced with an explosive ejection of rhyolitic tephra, followed by effusion of the mixed-magma dacitic flow, and ended with extrusion of rhyolitic lava at all vents along the fissure. Lava and pumice samples range from 61.3 to 74.6 percent silica and form linear to curvilinear arrays on variation diagrams. Quenched andesitic blobs (some with amphibole, Grove et al. 1977) are mainly in the dacitic lava flow, whereas the cumulate and granitoid fragments are found almost entirely in the distal domes near the ends of the fissure. The amphibole indicates high water contents in the parental andesitic magma, water that likely contributed to melting of granitic crust that combined with a rhyolitic differentiate to produce rhyolite. Compositional variation in the dacite and rhyolite requires at least three components. The dacite is a mixture of evolved rhyodacite (produced by fractionation of the parental andesite), a granitic crustal melt, and andesite containing olivine and An-rich plag. The dacite is charged with andesitic blobs, some of which may have intruded just prior to eruption. We interpret that before the eruption began, a zoned magma body formed at shallow depth, with rhyolitic magma at its top and dacitic magma underneath. Removal of rhyolitic magma during the initial explosive event allowed hotter and more fluid dacitic magma to enter and dominate the conduit resulting in effusion of the initial dacite flow. At times, rhyolitic melt remaining in the shallow reservoir squeezed into the conduit and was erupted as pods of obsidian (Anderson 1933) that

  1. 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.

  2. 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.

  3. 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.

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

    PubMed

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

    2011-10-01

    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). Ca(2+) leaching decreased in the North Tributary due to the SO(4)(2-) decrease, but this was partially offset by an increase in Ca(2+) leaching from increased DOC concentrations.

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

    PubMed

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

    2011-10-01

    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). Ca(2+) leaching decreased in the North Tributary due to the SO(4)(2-) decrease, but this was partially offset by an increase in Ca(2+) leaching from increased DOC concentrations. PMID:21741140

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Salting our Freshwater: A Macrosystems Study of Global Chloride Patterns and Trends in Lakes

    NASA Astrophysics Data System (ADS)

    Dugan, H.; Bartlett, S.; Burke, S.; Doubek, J.; Krivak-Tetley, F.; Skaff, N.; Summers, J.; Farrell, K.; McCullough, I.; Morales, A. M.; Roberts, D.; Yang, Z.; Scordo, F.; Hanson, P. C.; Weathers, K. C.

    2015-12-01

    Chloride is a naturally occurring ion in freshwater lakes that can have adverse ecological impacts if concentrations rise above natural background levels. Many lakes worldwide, including the Great Lakes, have seen increased chloride concentrations over the past few decades. Regional drivers include both natural processes (e.g., sea salt deposition and long periods of drought) and anthropogenic influences (e.g., runoff from road salt application and agricultural fertilizer and discharge of industrial effluent). While these trends and drivers have been studied at the watershed scale, there has been no large-scale analyses of chloride trends in freshwater lakes. Here, we have compiled a dataset of long-term (> 10 years) chloride concentrations in over 500 freshwater lakes, ponds and reservoirs worldwide (>0.04 ha), predominantly in the United States, Canada, Sweden, and the United Kingdom. The geographic and morphometric range of lakes in this dataset allows us to assess the impact of ecoregion, lake area, residence time, and lake depth on relative changes in chloride concentrations. For the United States, we combined our dataset with the National Land Cover Database and the National Hydrography Dataset to quantify percent impervious surface, as a proxy for road density, within the near-shore environment of our study lakes. We find that urban lakes, especially in the American Midwest (Wisconsin, Minnesota) have strong positive trends in chloride concentrations, whereas remote lakes, such as ponds in the Adirondack Mountains of New York, have had stable or decreasing chloride levels. In states with seasonal road-salt application, the percent impervious surface within 100 m of a lake is strongly correlated with increases in chloride. Road salt runoff is just one ecological threat to urban lakes, but can be abated with proper management.

  11. 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

  12. 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.

  13. 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.

  14. Distribution of polycyclic aromatic hydrocarbons in the food web of a high mountain lake, Pyrenees, Catalonia, Spain.

    PubMed

    Vives, Ingrid; Grimalt, Joan O; Ventura, Marc; Catalan, Jordi

    2005-06-01

    We investigated the contents of polycyclic aromatic hydrocarbons (PAHs) in the food web organisms included in the diet of brown trout from a remote mountain lake. The preferential habitat and trophic level of the component species have been assessed from the signature of stable isotopes (delta13C and delta15N). Subsequently, the patterns of accumulation and transformation of these hydrocarbons in the food chain have been elucidated. Most of the food web organisms exhibit PAH distributions largely dominated by phenanthrene, which agrees with its predominance in atmospheric deposition, water, and suspended particles. Total PAH levels are higher in the organisms from the littoral habitat than from the deep sediments or the pelagic water column. However, organisms from deep sediments exhibit higher proportions of higher molecular weight PAH than those in other lake areas. Distinct organisms exhibit specific features in their relative PAH composition that point to different capacities for uptake and metabolic degradation. Brown trout show an elevated capacity for metabolic degradation because they have lower PAH concentrations than food and they are enriched strongly in lower molecular weight compounds. The PAH levels in trout highly depend on organisms living in the littoral areas. Fish exposure to PAH, therefore, may vary from lake to lake according to the relative contribution of littoral organisms to their diet.

  15. 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.

  16. 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.

  17. Analysis and mitigation of remote geohazards in high mountain areas of Tajikistan with special emphasis on glacial lake outburst floods

    NASA Astrophysics Data System (ADS)

    Schneider, Jean F.; Mergili, Martin; Schneider, Demian

    2010-05-01

    Remote geohazard events in the mountains of Tajikistan have repeatedly caused disasters during the past decades. The rock avalanche of Khait in1949 and the glacial lake outburst flood (GLOF) in Dasht in 2002 are only two examples. However, the awareness among stakeholders and the local people is limited since the source areas are far away and the frequency of events is low. The major objective of the research outlined here is to identify and to highlight potential source areas and pathways of remote geohazard events, particularly of GLOFs, in order to allow for well-designed mitigation procedures. The geohazard assessment was carried out in a four-step procedure: • Pre-assessment: GIS and remote sensing techniques were employed for detecting potential source areas and pathways of remote geohazard processes. Relevant features were mapped from medium-resolution datasets and specific areas of interest were deducted from the mapping results. • Helicopter survey: the areas of interest identified during the Pre-assessment were screened from the helicopter. The knowledge gained this way was used to select the areas for the field assessment. • Field assessment: the areas of specific interest were visited in the field by international groups of 4 researchers. These areas were analyzed and mapped in detail and the level of hazard emanating from the lakes or slopes was estimated. • Post-assessment. Based on the field assessment, areas of particular hazard were selected for further analysis. Scenarios of dam breaks and flood waves were built and the possible impact farther down the valley was assessed using computer models. Based on that, recommendations how to mitigate the hazard will be given to the relevant agencies and stakeholders as well as to the local population. In the Southern Pamir, a number of growing glacial lakes was identified. Resulting flood waves could trigger process chains with catastrophic consequences for the population dozens of kilometres

  18. 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).

  19. 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). PMID:26186465

  20. Condition of Education in the Adirondack Blue Line.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany.

    This document profiles education in the Adirondack Park area of upstate New York. The introduction describes the Adironack Blue Line area, its school districts, and its revenues for school funding. Elementary and secondary education are described in terms of attendance rates, pupil-teacher ratio, teacher turnover rate, and median teacher salaries…

  1. VALUATION OF NATURAL RESOURCE IMPROVEMENTS IN THE ADIRONDACKS

    EPA Science Inventory

    The benefits of improving natural resources in the Adirondacks are estimated to be between $336 million and $1.1 billion per year (2003$), according to a new study by Resources for the Future. The five-year study, supported by an EPA grant, estimates New Yorkers willingness-to-...

  2. 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. PMID:27207135

  3. The Sources of Carbon and Nitrogen in Mountain Lakes and the Role of Human Activity in Their Modification Determined by Tracking Stable Isotope Composition.

    PubMed

    Gąsiorowski, Michał; Sienkiewicz, Elwira

    2013-04-01

    We studied the isotopic composition of organic matter in the sediments of eight mountain lakes located in the Tatra Mountains (Western Carpathians, Poland). The sediments of the lakes were fine and course detritus gyttja, mud, and sand. The total organic carbon content varied from 0.5 to 53 %. The C/N ratio indicated that in-lake primary production is the major source of the organic matter in the lakes located above the treeline, whereas terrestrial plant fragments are the major organic compounds in the sediments of dystrophic forest lakes. We also found that a clear trend of isotopic curves toward lower values of δ (13)C and δ (15)N (both ~3 ‰) began in the 1960s. This trend is a sign of the deposition of greater amounts of NO x from the combustion of fossil fuels, mainly by vehicle engines. The combustion of fossil fuels in electric plants and other factories had a smaller influence on the isotopic composition. This trend has been weaker since the 1990s. Animal and human wastes from pastures and tourism had a surprisingly minor effect on lake environments. These data are contrary to previous data regarding lake biota and suggest the high sensitivity of living organisms to organic pollution. PMID:23576824

  4. The Sources of Carbon and Nitrogen in Mountain Lakes and the Role of Human Activity in Their Modification Determined by Tracking Stable Isotope Composition.

    PubMed

    Gąsiorowski, Michał; Sienkiewicz, Elwira

    2013-04-01

    We studied the isotopic composition of organic matter in the sediments of eight mountain lakes located in the Tatra Mountains (Western Carpathians, Poland). The sediments of the lakes were fine and course detritus gyttja, mud, and sand. The total organic carbon content varied from 0.5 to 53 %. The C/N ratio indicated that in-lake primary production is the major source of the organic matter in the lakes located above the treeline, whereas terrestrial plant fragments are the major organic compounds in the sediments of dystrophic forest lakes. We also found that a clear trend of isotopic curves toward lower values of δ (13)C and δ (15)N (both ~3 ‰) began in the 1960s. This trend is a sign of the deposition of greater amounts of NO x from the combustion of fossil fuels, mainly by vehicle engines. The combustion of fossil fuels in electric plants and other factories had a smaller influence on the isotopic composition. This trend has been weaker since the 1990s. Animal and human wastes from pastures and tourism had a surprisingly minor effect on lake environments. These data are contrary to previous data regarding lake biota and suggest the high sensitivity of living organisms to organic pollution.

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

    NASA Astrophysics Data System (ADS)

    Cronan, Christopher S.; Aiken, George R.

    1985-08-01

    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 μeq mg-1 C at ambient pH, and a total of 6-7 meq COOH per gram carbon.

  6. 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.

  7. Holocene Lake Productivity and Inferred Climate Histories From High-Altitude Sites Within the Baroon Taiga Mountains, Northern Mongolia

    NASA Astrophysics Data System (ADS)

    Robinson, K. D.; Rosenmeier, M. F.; Ortiz, J. D.

    2007-12-01

    Diffuse reflectance spectroscopy, biogenic silica, and standard loss-on-ignition (LOI) analyses of radiocarbon- dated sediment core samples from Sanjin, Asgat, Ganbold, and Mustei Nuur provide a nearly 11,000 year history of aquatic productivity changes within lakes of the Baroon Taiga Mountains, northern Mongolia. Productivity within these lakes is most sensitive to temperature fluctuations because the catchments are small, nutrient poor, and located at relatively high elevations (greater than 2200 m) with very low annual average temperatures. Within the Mustei Nuur basin, long-term decreases in reflectance and LOI-inferred algal productivity follow orbitally-forced reductions in northern hemisphere solar insolation (i.e., energy receipt) after 8000 years before present (B.P.). Prior to 8000 years ago, enhanced algal productivity within the lake likely reflects increasing northern hemisphere temperature trends following late glacial conditions. Higher frequency (decadal to centennial-scale) changes in biogenic silica, organic matter, and reflectance-inferred algal pigment concentrations within the late Holocene sediment sequences of Sanjin, Asgat, and Ganbold Nuur are interpreted as representing aquatic productivity variations influenced by the length of the ice-free growing season and, by further inference, local temperature variations. Reduced productivity and inferred lower temperatures are documented between 300 and 100 years B.P., roughly coincident with the Little Ice Age, whereas warmer conditions existed from 900-1100 years B.P., and between (roughly) 100 years B.P. and the present. Inferred warming over the last century parallels instrumental data trends, numerous high-latitude (arctic) paleoenvironmental records, and several other notable northern hemisphere temperature reconstructions. Correlations between late Holocene reflectance, biogenic silica, and LOI-inferred aquatic productivity records from the Baroon Taiga alpine lakes and nearby temperature

  8. SRTM Perspective View with Landsat Overlay: Syracuse, Oneida Lake, Upstate New York

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In the lower center of this perspective view of upstate New York, the city of Syracuse hugs the southeastern banks (top right side) of Lake Onondaga, the smaller of the two dark features that dominate the scene. The view is toward the east. The urban area appears bright in stark contrast to the dark waterways and the greens, browns and yellows of the vegetated areas. Both of the two black features are lakes. Oneida Lake , the larger of the two is to the left of the scene center. About 1/3 of the way between Lakes Onondaga and Oneida are the triangular shaped runways of the Syracuse Hancock International Airport. The Adirondack Mountains are to the upper left while the less rugged Catskills can be seen in the upper right. A faint outline of the Mohawk River can be seen as threads its way down from the Adirondacks toward the city of Rome, the bright area in the valley between the lake and the Adirondacks. The Erie Canal and the Oswego River are part of the network of waterways seen in the left image foreground.

    Fall foliage in a variety of colors can be seen in the Landsat data used here. Redder vegetation generally occurs at higher elevations and toward the north (left), especially in the Adirondack Mountains. The back edge of the data set forms a false skyline. The image was generated using topographic data from SRTM and enhanced true-color Landsat 5 satellite images. Topographic shading in the image was enhanced with false shading derived from the elevation model. Topographic expression is exaggerated 6X. Syracuse lies at the geographic center of the state of New York and has been the site of its state fair for most of that event's 154 years. It is located in an agricultural and resort area. The yellowish rectangular features in the foreground of the image are farmlands. Parts of Skaneateles and Otisco Lakes, some of central New York's Finger Lakes, can be seen in the bottom right corner of the image.

    Elevation data used in this image was acquired by

  9. Late Holocene Central Asia environmental change as evidenced in high-resolution continental archives - mountain lakes and tree-rings

    NASA Astrophysics Data System (ADS)

    Darin, A.; Kalugin, I.; Maksimova, N.; Ovchinikov, D.

    2009-04-01

    Cores of bottom sediments from Teletskoe Lake (Mountain Altai) and Telmen Lake (North Mongolia) were investigated by method of scanning X-ray fluorescent analysis with synchrotron radiation with the spatial resolution of 0.1 mm [1, 2]. It corresponds to the time resolution ~ 0.2-0.3 year (sedimentation rates are equal 0.51 mm/year for Teletskoe Lake and 0.64 mm/year for Telmen Lake [3, 4]). Geochemical proxy of terrigenous, organogenous and aerosol components of sediments well correlated with regional meteodata. Quantitative reconstruction of climatic parameters were constructed using the transfer functions such as: sediment composition=function (temperature, precipitation). Functions have been calibrated at the historic interval of the cores over the last 80-120 years. Dendro samples were collected in adjacent lakes areas. The joint processing of the results helped us to clarify the time-series of geochemical proxies, adjustments based on dendro climate signals. Annual temperature and precipitation change for the Altai region (0 - 3000 years ago) and Northern Mongolia region (0 - 2000 years ago) have been reconstructed. A Fourier analysis showed the same frequency of climate change for both regions. Have been identified as the main periods (frequency): 2000, 1000, 660, 500, 400, 330, 270, 200, 155, 125, 105, 80, 45, 30 and 10 years. Based on the discovered periodicities forecast the environment change for the period 2010-2050 was calculated. According to our estimates at this time is expected sharp fall of annual regional temperature. The study was funded by grant 07-05-92103 from the Russian Foundation for Basic Research. [1] K. Zolotarev et all. Scanning SR-XRF beamline for analysis of bottom sediments. // Nucl. Instrum. and Meth. in Physics Research, A470 (2001), 1-2 , P.376-379. [2] A. Daryin et all. Use of a scanning XRF analysis on SR beams from VEPP-3 storage ...// Nucl. Instrum. and Methods in Physics Research A 543 (2005) 255-258. [3] I. Kalugin et all

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 78 FR 69363 - Lake Tahoe Basin Management Unit, California, Heavenly Mountain Resort Epic Discovery Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ...The Epic Discovery Project is intended to enhance summer activities in response to the USDA Forest Service Ski Area Recreational Opportunity Enhancement Act of 2011. Heavenly Mountain Resort (Heavenly) proposes to improve year-round, recreation opportunities within the developed portions of the ski area on National Forest System lands using existing facilities and infrastructure to meet the......

  16. 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.

  17. New lakes in deglaciating high-mountain areas: Regional intercomparison of current and future risks from impact waves due to rock/ice avalanches in the Swiss Alps

    NASA Astrophysics Data System (ADS)

    Schaub, Y.; Huggel, C.; Serraino, M.; Haeberli, W.

    2012-04-01

    The changes in high-mountain environments are increasingly fast and complex. GIS-based models of the Swiss Alps show that numerous topographic overdeepenings are likely to appear on progressively exposed glacier beds, which are considered as potential sites of future lake formation. In many cases these newly forming lakes will be situated in an over-steepened and destabilized high-mountain environment and are, therefore, prone to impact waves from landslides. The risk of glacier lake outburst floods, endangering infrastructure, residential areas and persons further downvalley, is increasing with further lake formation and glacier recession. This risk may persist for many decades if not centuries. Future-oriented hazard assessments have to be integrative and must deal with all possible process chains. Reference studies and methodologies are still scarce, however. We present an approach to compare risks resulting from high-mountain lakes in the Swiss Alps amongst each other. Already existing lakes are thereby as much included in the analysis as future ones. The presented risk assessment approach integrates the envisaged high-mountain hazard process chain with present and future socio-economic conditions. Applying the concept of integral risk management, the hazard and damage potentials have to be analyzed. The areas that feature the topographic potential for rock/iceavalanches to reach a lake were analyzed regarding their susceptibility to slope failure including the factors slope inclination, permafrost occurrence, glacier recession and bedrock lithology. Together with the analysis of the lakes (volume and runout path of potential outburst floods), the hazard analysis of the process chain was completed. As an example, high long-term hazard potentials in the Swiss Alps have, for instance, to be expected in the area of the Great Aletsch glacier. A methodology for the assessment of the damage potential was elaborated and will be presented. In order to estimate the

  18. 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.

  19. 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.

  20. 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.

  1. 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

  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. 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.

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

    NASA Astrophysics Data System (ADS)

    Chachere, Catherine N.; Pu, Zhaoxia

    2016-05-01

    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.

  5. Pennsylvanian fusulinids from the Beaverhead Mountains, Morrison Lake area, Beaverhead County, Montana

    SciTech Connect

    Verville, G.J. ); Sanderson, G.A.; Baesemann, J.F. ); Hampton, G.L. III )

    1990-04-01

    A fusulinid fauna consisting of Triticites spp., Kansanella aff. K. tenuis (Merchant Keroher), Eowaeringella sp., Fusulina sp. (Beedeina of some authors), Wedekindellina henbesti (Skinner), Plectofusulina spp., Pseudostaffella sp., Fusulinella aff. F. acuminata Thompson, and Eoschubertella sp. has been identified from Pennsylvanian rocks exposed on the Continental Divide, Morrison Lake area, Beaverhead County, Montana. These fusulinids, the first to be published from Pennsylvanian rocks in southwestern Montana, indicate that strata of late Atokan, early Desmoinesian, Missourian, and Virgilian age are present. These rocks, previously assigned to the Quadrant Formation in the Morrison Lake area, are subdivided and correlated with the Bloom, Gallagher Peak Sandstone and Juniper Gulch members of the Snaky Canyon Formation (Skipp et al., 1979a).

  6. 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.

  7. 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

  8. 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

  9. 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…

  10. Air-water gas exchange of chlorinated pesticides in four lakes spanning a 1,205 meter elevation range in the Canadian Rocky Mountains.

    PubMed

    Wilkinson, Andrew C; Kimpe, Lynda E; Blais, Jules M

    2005-01-01

    Concentrations of selected persistent organic pollutants (POPs) in air and water were measured from four lakes that transect the Canadian Rocky Mountains. These data were used in combination with wind velocity and temperature-adjusted Henry's law constants to estimate the direction and magnitude of chemical exchange across the air-water interface of these lakes. Bow Lake (1,975 m above sea level [masl]) was studied during the summers of 1998 through 2000; Donald (770 masl) was studied during the summer of 1999; Dixon Dam Lake (946 masl) and Kananaskis Lake (1,667 masl) were studied during the summer of 2000. Hexachlorobenzene (HCB) and dieldrin volatilized from Bow Lake in spring and summer of 1998 to 2000 at a rate of 0.92 +/-1.1 and 0.55+/-0.37 ng m(-2) d(-1), respectively. The alpha-endosulfan deposited to Bow Lake at a rate of 3.4+/-2.2 ng m(-2) d(-1). Direction of gas exchange for gamma-hexachlorocyclohexane (gamma-HCH) changed from net deposition in 1998 to net volatilization in 1999, partly because of a surge in y-HCH concentrations in the water at Bow Lake in 1999. Average gamma-HCH concentrations in air declined steadily over the three-year period, from 0.021 ng m(-3) in 1998, to 0.0023 ng m(-3) in 2000, and to volatilization in 1999 and 2000. Neither the concentrations of organochlorine compounds (OCs) in air and water, nor the direction and rate of air-water gas exchange correlate with temperature or elevation. In general, losses of pesticides by outflow were greater than the amount exchanged across the air-water interface in these lakes. PMID:15683168

  11. 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

  12. 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.

  13. 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

  14. Long-term trends and spatial variability in nitrate leaching from alpine catchment-lake ecosystems in the Tatra Mountains (Slovakia-Poland).

    PubMed

    Kopácek, Jirí; Stuchlík, Evzen; Wright, Richard F

    2005-07-01

    Relationships between catchment characteristics of 31 alpine lakes and observed trends in lake water concentrations of nitrate were evaluated in the Tatra Mountains. Nitrate concentrations increased from background levels <4 microeql(-1) in the 1930s to maxima (up to 55 microeql(-1)) in the 1980s, after which they declined to 4-44 microeql(-1) by the late 1990s. In-lake nitrate concentrations correlated negatively with parameters characterising catchment-weighted mean pools (CWM; kgm(-2)) of soil, i.e. with percent land cover with meadow and soil depth, and positively with grade of terrain, annual precipitation, and the highest elevation in the catchment. The CWM pool of soil and annual precipitation explained together 65% of the current spatial variability in nitrate concentrations. Denitrification and direct N deposition on surface area explained 14% of the variability. Increased atmospheric N deposition and declining net N retention in soils were responsible for long-term changes in nitrate concentrations. Long-term decline in %N retention in soils decreased along with the estimated decline in C:N ratios (from 21 to 18 on average during the last 70 years). An empirical model linking nitrate concentrations in different types of alpine Tatra Mountain lakes to four independent variables (CWM soil pool, annual precipitation, increased N deposition, and average trend in soil C:N ratios) explained 80% of the observed spatial and temporal nitrate variability over the period 1937-2000.

  15. Altitudinal and thermal gradients of hepatic Cyp1A gene expression in natural populations of Salmo trutta from high mountain lakes and their correlation with organohalogen loads.

    PubMed

    Jarque, Sergio; Gallego, Eva; Bartrons, Mireia; Catalan, Jordi; Grimalt, Joan O; Piña, Benjamin

    2010-05-01

    The biomarker of xenobiotic exposure cytochrome p450A1 (Cyp1A) was used to analyze the biological response to chemical pollution in Salmo trutta (brown trout) from nine high mountain European lakes in Norway, Tatras, Tyrol, and central Pyrenees. Hepatic Cyp1A mRNA levels correlated both with the reciprocal of absolute annual average air temperatures of the sampled lakes and with muscle concentrations of several hydrophobic organohalogen compounds (OC), including chlorinated polychlorobiphenyls (PCB), DDE, and DDT. The correlation between Cyp1A expression and OC content was observed across the whole temperature range (between -0.7 degrees C and +6.2 degrees C), but also in the absence of any thermal gradient. We concluded that airborne pollutants accumulate in high mountain lake fish at concentrations high enough to increase Cyp1A expression, among other possible effects. As geographical distribution of semi-volatile OC is strongly influenced by air temperatures, future climate modifications will potentially enhance their physiological effects in lake ecosystems.

  16. 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

  17. Thermal stratification of Dilute Lakes. Evaluation of regulatory processes and biological effects before and after base addition: Effects on brook trout habitat and growth. Technical report series

    SciTech Connect

    Schofield, C.L.; Josephson, D.; Keleher, C.; Gloss, S.P.

    1993-04-01

    The authors address the significance of changes in summer thermal stratification patterns of Adirondack lakes affected by acidification to cold-water fish populations inhabiting these sensitive lakes. The brook trout (Salvelinus fontinalis) is the primary cold-water fish species indigenous to acid-sensitive lakes in the Adirondack region of northern New York State; the ability of these lakes to sustain this important sport species is highly dependent on the availability of adequate summer habitat, consisting of cool, well-oxygenated water. The authors hypothesized that acidification-induced reductions in the thermal stability of sensitive Adirondack lakes could lead to degradation of potential brook trout habitat. These hypotheses were addressed in the study by utilizing data available from previous lake liming studies in the Adirondack region, brook trout growth data from management studies in the region, and the extensive Adirondack Lake Survey Corporation (ALSC) data base. More than 70% of the small, shallow ALSC lakes were classified as predominantly weakly stratified systems that would be potentially sensitive to changes in thermal stratification status resulting from relatively small changes in color and transparency.

  18. 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

  19. Effects of Past Climate Changes on Ecosystem Biogeochemical Cycles in Rocky Mountain Forests and Lakes

    NASA Astrophysics Data System (ADS)

    Shuman, B.; Mechenich, M. F.; Stefanova, I.; Henderson, A.; Donnelly, J. P.

    2007-12-01

    Ongoing climate trends will likely alter how forest ecosystems produce important goods and services, in part, by changing ecosystem responses to disturbances, such as fires and land-use. Disturbances induce forest succession and thus dramatically change the flow of water and nutrients through a given ecosystem. However, long-term ecosystem responses to disturbance, especially regarding nutrient pools and cycling rates, are poorly documented, and less is known about the effects of century-scale climate trends on these responses especially with respect to moisture. Here, we show biogeochemical responses to repeated (>20) episodes of disturbance and succession in a single ecosystem under a range of climatic conditions over 2000 years. Our lake sediment record shows regular fluctuations in the flux of base cations and other macronutrients from lodgepole pine ( Pinus contorta) forests in northern Colorado following catastrophic stand-replacing fires. Post-fire elemental fluctuations are consistent with ecosystem theory regarding the re-equilibration of biomass and nutrient pools during succession, but show systematic variation that has been previously undocumented. The time span of post-fire re-equilibration correlates positively with measures of fire severity, which is consistent with hypotheses that seed dispersal and soil recovery likely slow re-growth after large or severe fires. Likewise, dry conditions during the Medieval Climatic Anomaly (MCA, 1200-500 yrs BP) altered elemental fluctuations and, thus, generated post-fire pulses of lake eutrophication that were not evident during other periods. The interaction of climate and disturbance, therefore, has important consequences for ecosystem function and services, including the quality of aquatic environments.

  20. Seismic stratigraphy of Waterton Lake, a sediment-starved glaciated basin in the Rocky Mountains of Alberta, Canada and Montana, USA

    NASA Astrophysics Data System (ADS)

    Eyles, Nicholas; Boyce, Joseph I.; Halfman, John D.; Koseoglu, Berkant

    2000-02-01

    Upper and Middle Waterton lakes fill a glacially scoured bedrock basin in a large (614 km 2) watershed in the eastern Front Ranges of the Rocky Mountains of southern Alberta, Canada and northern Montana, U.S.A. The stratigraphic infill of the lake has been imaged with 123 km of single-channel FM sonar (`chirp') reflection profiles. Offshore sonar data are combined with more than 2.5 km of multi-channel, land-based seismic reflection profiles collected from a large fan-delta. Three seismic stratigraphic successions (SSS I to III) are identified in Waterton Lake resting on a prominent basal reflector (bedrock) that reaches a maximum depth of about 250 m below lake level. High-standing rock steps (reigels) divide the lake into sub-basins that can be mapped using lake floor reflection coefficients. A lowermost transparent to poorly stratified seismic succession (SSS I, up to 30 m thick) is present locally between bedrock highs and has high seismic velocities (1750-2100 m/s) typical of compact till or outwash. A second stratigraphic succession (SSS II, up to 50 m thick), occurs throughout the lake basin and is characterised by continuous, closely spaced reflectors typical of repetitively bedded and rhythmically laminated silts and clays most likely deposited by underflows from fan-deltas; paleo-depositional surfaces identify likely source areas during deglaciation. Intervals of acoustically transparent seismic facies, up to 5 m thick, are present within SSS II. At the northern end of Upper Waterton Lake, SSS II has a hummocky surface underlain by collapse structures and chaotic facies recording the melt of buried ice. Sediment collapse may have triggered downslope mass flows and may account for massive facies in SSS II. A thin Holocene succession (SSS III, <5 m) shows very closely spaced reflectors identified as rhythmically laminated fine pelagic sediment deposited from interflows and overflows. SSS III contains Mt. Mazama tephra dated at 6850 yr BP.

  1. Tectonic and climate changes expressed as sedimentary cycles and stratigraphic sequences of the Paleogene Lake Uinta System, central Rocky Mountains, Utah and Colorado

    SciTech Connect

    Fouch, T.D.; Pitman, J.K.

    1991-03-01

    Lake Uinta strata record both long- and short-term changes in climate and tectonic regime. Late Paleocene to late Eocene deposits are characterized by evaporite units (including halite and bicarbonate salts) and organically derived carbonate with extreme positive {delta}{sup 13}C and slightly negative {delta}{sup 18}O values that serve as evidence the lake was the center of a closed hydrologic system. Large reconfigurations of the lake system were tectonically induced and gave rise to relatively thick, lithologically distinct stratigraphic sequences. Simultaneous climate changes initiated very rapid lake level expansions and contractions as well as shifts in lake-water alkalinity and salinity (or chemistry) which resulted in the development of small- to large-scale sedimentary and stratigraphic cycles. Maastrichtian to earliest Eocene phases formed in local depressions (piggy back basins) on the thrust sheets, and in the incipient Uinta basin. Lake system reached its greatest aerial and volumetric extent in the middle and late Eocene and was centered in the foreland formed in front of high-angle reverse faults that bounded the rising Laramide structural blocks. At this time chemical precipitates, including basin centered carbonate and evaporite facies, formed during episodes of tectonically induced subsidence at the center of the clastic sediment-starved basin. Some fault-bounded margins of the Uinta basin are marked by synorogenic coarse debris that extends from the mountain front to the clastic sediment-starved lake. Tectonically induced stratigraphic sequences of the Lake Uinta system express environments for several million years whereas climatic cycles reflect much shorter episodes and very rapidly changing conditions.

  2. Increased Calcium Availability Leads to Greater Forest Floor Accumulation in an Adirondack Forest

    NASA Astrophysics Data System (ADS)

    Melvin, A.; Goodale, C. L.

    2010-12-01

    Nutrient availability in Northeastern US forests has been dramatically altered by anthropogenic activities. Acid deposition has not only increased nitrogen (N) availability, but has also been linked to soil acidification and a loss of base cations, largely calcium (Ca). We are studying the long-term effects of a Ca addition on carbon (C) and N cycling in a forested catchment in the Adirondack Park, New York. In 1989, calcium carbonate (lime) was added to two subcatchments within the Woods Lake Watershed to ameliorate the effects of soil Ca depletion. Two additional subcatchments were left as controls. Eighteen years after the Ca application, both soil pH and exchangeable Ca concentrations remain elevated in the organic horizons and upper mineral soils of the treated subcatchments. The forest floor mass in this watershed is very large and measurements show that the organic layer in the limed subcatchments is significantly larger than in the controls (212 t/ha vs. 116 t/ha), resulting in greater C and N stocks in the Ca-amended soils. This finding suggests that Ca may stabilize soil organic matter (SOM), resulting in greater C storage under high soil Ca conditions. We are investigating potential drivers of this SOM accumulation in the limed subcatchments, including rates of leaf litter production and the decomposition rate of forest floor material. This work will provide important insights into how long-term changes in soil Ca availability influence SOM stabilization, retention and nutrient cycling.

  3. 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.

  4. 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

  5. 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

  6. 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

  7. 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.

  8. Application of the PnET-BGC - An integrated biogeochemical model - To assess the surface water ANC recovery in the Adirondack region of New York under three multi-pollutant proposals

    NASA Astrophysics Data System (ADS)

    Wu, Wei; Driscoll, Charles T.

    2009-11-01

    SummaryWe applied an integrated biogeochemical model PnET-BGC to predict the response of acid neutralizing capacity (ANC) in lakes - a measure of the ability of water to neutralize inputs of strong acid - from 2001 to 2050 in the Adirondack region of New York, USA under three multi-pollutant proposal scenarios. Through model predictions, we assessed the impacts of these proposals on ecosystem recovery for research and policy initiatives. Our analysis indicated that the predicted recovery rates of surface water ANC obtained from the PnET-BGC model show low spatial autocorrelation. Predicted recovery rates are also closely related with the percentage of watershed areas of coniferous vegetation and deciduous vegetation, elevation and lake area, which turn out not to be significantly different from each other over the entire period of future scenarios (2001-2050). We applied a Geographic Weighted Regression model (GWR) to study the spatial patterns of predicted lake ANC in the Adirondacks through 2050 due to its high spatial autocorrelation. These results showed that lake depth and square of elevation can explain 40% of variation in the predicted ANC, which is 26% more variation than explained by the non-spatial Ordinary Least-Squares Regression (OLS). Our calculations also suggest that even under the Carper Bill, the most aggressive air pollutant control scenario considered, not all Adirondack lakes will recover (i.e., ANC > 50 μeq/L) from elevated acidic deposition by 2050. The research provides a basis for more informed emission controls and land use/land cover (LULC) policy-making in the north-eastern USA and elsewhere.

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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

  16. 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

  17. 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.

  18. Moving Mountains and Deep Crustal Earthquakes: Evidence for Deep Magma Injection Beneath Lake Tahoe, Nevada-California

    NASA Astrophysics Data System (ADS)

    Blewitt, G.; Smith, K. D.; von Seggern, D.

    2004-12-01

    We recently reported [Smith et al., Science 305, 2004] an unusually deep swarm of 1611 earthquakes that occurred in late 2003 at Lake Tahoe, California (depth 29-33 kilometer; Richter Magnitude [ML] < 2.2; sum of the moment magnitude of all events is Mw 3.1). This swarm was coeval with a GPS transient displacement of 6 ± 0.3 mm horizontally outward from the swarm and 7.9 ± 1.0 mm upward measured at the GPS station on Slide Mountain, Nevada (SLID) 18 km to the northeast. Station SLID is a part of the 53-station Basin and Range Geodetic Network (BARGEN) network, continuously operating since 1996 and one of the PBO Nucleus stations. Here we focus on the results of the geodetic analysis for SLID, and other BARGEN stations within 200 km of SLID, starting on 1 January 2000. The SLID transient displacement is 9.8 mm in a direction normal to the planar structure defined by the deep earthquake swarm, spanning the same time period of the swarm. The geodetic displacement here is too large to be explained by the elastic strain from the cumulative seismic moment of the sequence, suggesting an aseismic forcing mechanism. Aspects of the swarm and SLID displacements are consistent with lower-crustal magma injection under Lake Tahoe. During the first 23 days of the swarm, hypocentral depths migrated at a rate of 2.4 millimeters/second up-dip along a 40-km2 structure striking N30° W and dipping 50° to the northeast. Assuming a stress drop of 10 MPa (reasonable for upper crustal earthquakes), this event has an equivalent seismic moment to a magnitude (Mw) 6.0 earthquake with a displacement of ~1 meter at the source. Applying Okada's model for a tensile crack at 28 km depth in the source region, a potency equivalent to a volume of 3.7 × 107 m3, or volumetric moment equivalent of Mw 6.4, fits the SLID observations. As there is no established evidence of recent volcanism (<1 Ma) in the Tahoe region, this discovery suggests the hypothesis that such deep magmatic events in

  19. 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.

  20. 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.

  1. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-10-01

    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.

  3. 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.

  4. 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. PMID:27315168

  5. 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.

  6. 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.

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

    PubMed Central

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

    2016-01-01

    Summary 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 × 105 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. PMID:25756115

  8. 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. PMID:26747996

  9. 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.

  10. Assessing trends in fishery resources and lake-water aluminum from paleolimnological analyses of siliceous algae

    SciTech Connect

    Kingston, J.C.; Birks, H.J.B.; Uutala, A.J.; Cummings, B.F.; Smol, J.P.

    1992-01-01

    Lake water aluminum concentrations have a significant influence on the composition of microfossil assemblages of diatoms and chrysophytes deposited in lake sediments. With the paleolimnological approach of multilake datasets in the Adirondack region of New York, USA, the authors use canonical correspondence analysis to describe past trends in lake water Al. Four lakes, previously investigated regarding acidification and fishery trends, are used to demonstrate that paleolimnological assessment can also provide direction, timing, and magnitude of trends for both toxic metals and fish resources. Additionally, the authors use weighted average regression and calibration to obtain quantitative reconstructions of past lake water Al concentrations. Such reconstructions provide further insight into fishery resource damage and can be compared with modelling results. According to paleolimnological reconstructions, some of the naturally most acidic lakes in the Adirondack region had preindustrial lake water concentrations of inorganic monomeric Al near 4/micromol times L. Although these high concentrations are surprising from a geochemical point of view, they may partially explain the preindustrial absence of fish, as has been independently determined by paleolimnological analysis of phantom midges (Chaoborus). Fishery resource deterioration in acidified Adirondack lakes was coincident with major increases in lake water Al concentrations.

  11. 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

  12. Utah: Salt Lake City

    Atmospheric Science Data Center

    2014-05-15

    ... backdrops for the 2002 Winter Olympics, to be held in Salt Lake City, Utah. The mountains surrounding Salt Lake City are renowned for ... western edge of the Rocky Mountains and eastern rim of the Great Basin. This early-winter image pair was acquired by the Multi-angle ...

  13. 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

  14. 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

  15. Modeling and mapping of atmospheric mercury deposition in adirondack park, new york.

    PubMed

    Yu, Xue; Driscoll, Charles T; Huang, Jiaoyan; Holsen, Thomas M; Blackwell, Bradley D

    2013-01-01

    The Adirondacks of New York State, USA is a region that is sensitive to atmospheric mercury (Hg) deposition. In this study, we estimated atmospheric Hg deposition to the Adirondacks using a new scheme that combined numerical modeling and limited experimental data. The majority of the land cover in the Adirondacks is forested with 47% of the total area deciduous, 20% coniferous and 10% mixed. We used litterfall plus throughfall deposition as the total atmospheric Hg deposition to coniferous and deciduous forests during the leaf-on period, and wet Hg deposition plus modeled atmospheric dry Hg deposition as the total Hg deposition to the deciduous forest during the leaf-off period and for the non-forested areas year-around. To estimate atmospheric dry Hg deposition we used the Big Leaf model. The average atmospheric Hg deposition to the Adirondacks was estimated as 17.4 [Formula: see text]g m[Formula: see text] yr[Formula: see text] with a range of -3.7-46.0 [Formula: see text]g m[Formula: see text] yr[Formula: see text]. Atmospheric Hg dry deposition (370 kg yr[Formula: see text]) was found to be more important than wet deposition (210 kg yr[Formula: see text]) to the entire Adirondacks (2.4 million ha). The spatial pattern showed a large variation in atmospheric Hg deposition with scattered areas in the eastern Adirondacks having total Hg deposition greater than 30 μg m(-2) yr(-1), while the southwestern and the northern areas received Hg deposition ranging from 25-30 μg m(-2) yr(-1).

  16. 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

  17. Compound-Specific Stable Isotopes of Organic Compounds From Lake Sediments Track Recent Environmental Changes in an Alpine Ecosystem, Rocky Mountain National Park, Colorado (United States of America)

    NASA Astrophysics Data System (ADS)

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

    2007-12-01

    Sediments from high altitude lakes in the North American Cordillera reveal rapid changes in both the composition of diatom communities and bulk organic δ15N over the past c. 60 years. In this study, compound- specific nitrogen, carbon, and hydrogen isotope records from Sky Pond, an alpine lake in Rocky Mountain National Park (Colorado, United States of America), were used to identify the factors contributing to ecological change. Our results from the nitrogen isotopic compositions of purified algal chlorins indicate that the magnitude of isotopic change is larger than implied from bulk organic δ15N, and support a substantial shift in nitrogen (N)-cycling in the region. Temporal changes in the growth characteristics of lichen surrounding Sky Pond, as well as a -60‰ excursion in δD values of algal-derived palmitic acid, are coincident with changes in N-cycling, indicating alterations in catchment hydrology and nutrient delivery. The confluence of these trends is attributed to an increase in anthropogenic N deposition caused by both expansion anthropogenic influences and temporal changes in regional hydrology associated with snow, glacier, and permafrost melt.

  18. 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.

  19. 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.

  20. 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.

  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. Perspective View, New York State, Long Island to Lake Ontario

    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 perspective view shows the varied topography of eastern New York State and parts of Massachusetts, Connecticut, Pennsylvania, New Jersey and Rhode Island. The high'bumpy' area in the upper right is the southern and western Adirondack Mountains, a deeply eroded landscape that includes the oldest rocks in the eastern United States. On the left side are 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, a wide valley contains the Mohawk River and the Erie Canal. To the northwest (upper left) 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 area 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 Berkshire Hills are between the Hudson and Connecticut valleys.

    This image was generated using a single swath of data acquired in 68 seconds by SRTM and an enhanced false-color mosaic of images from the Landsat 5 satellite. Lush vegetation appears green, water appears dark blue, and cities are generally light blue. White clouds occur in the upper right and lower right. Topographic shading in the image was enhanced with false shading derived from the elevation model. Topographic expression is exaggerated 5X.

    Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar

  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. 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

  5. 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.

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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.

  13. Perspective View, 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 bottom of the image) and extending to Long Island (at the top), this perspective view shows the varied topography of eastern New York State and parts of Massachusetts, Connecticut, Pennsylvania, New Jersey and Rhode Island. The high 'bumpy' area in the left foreground is the southern and western Adirondack Mountains, a deeply eroded landscape that includes the oldest rocks in the eastern United States. On the right side are 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, A wide valley contains the Mohawk River and the Erie Canal. To the northwest (lower right) of the Catskills are the Finger Lakes of central New York . They were carved by the vast glacier that covered this entire area as recently as 18,000 years ago. The Hudson River runs along a straight valley from left center (near Glens Falls), widening out as it approaches New York City at the upper right on the image. The Connecticut River valley has a similar north-south trend further to the east (across the upper left corner of the image). The Berkshire Hills are between the Hudson and Connecticut valleys.

    This image was generated using a single swath of data acquired in 68 seconds by SRTM and an enhanced false-color mosaic of images from the Landsat 5 satellite. Lush vegetation appears green, water appears dark blue, and cities are generally light blue. White clouds occur in the upper left and lower left. Topographic shading in the image was enhanced with false shading derived from the elevation model. Topographic expression is exaggerated 5X.

    Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR

  14. 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.

  15. 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

  16. LANDSAT applications by the Adirondack Park Agency for land cover analyses and forest cover change

    NASA Technical Reports Server (NTRS)

    Banta, J. S.; Curran, R. P.

    1981-01-01

    The New York State Adirondack Park Agency is using LANDSAT imagery to provide current, consistent parkwide data on forest cover, forest change and other land cover characteristics for the Adirondack Park, an area of 9,375 sq. miles (24,280 sq km). Boundaries of the study area were digitized and the data were enhanced and geographically rectified. A classification scheme was devised which emphasized the basic land cover types of the Park: hardwoods, spruce-fir, pine, wet conifer, brushland, grassland, agricultural areas, exposed earth, urban areas, and water bodies. Cover type classifications for disturbed forest land were also chosen: cut hardwoods, regenerating hardwoods, and cut spruce fir. Field verification of 1978 classification revealed an accurate differentiation of forest types within types and between nonforested/forested areas. The classification accurately detects forest land disturbances; however, it is not always descriptive of the level of disturbance.

  17. A Discussion of the Area Method for Hydrograph Separation, Case Study in the Adirondacks, New York State (USA)

    NASA Astrophysics Data System (ADS)

    Jutras, B. A.; Romanowicz, E. A.

    2004-05-01

    Many hydrology texts refer to the area method for estimating the end of surface runoff after the peak discharge in storm hydrographs. This method is used to aid in separating base flow from surface runoff in stream flow during storm events. The area method assumes that the duration of surface runoff after peak discharge is a function of the area of the drainage basin. The duration of surface runoff in days is equal to the area of the drainage basin (sq. miles) raised to the 0.2 power. References to the type of watersheds for which this relationship is true are vague. The method is assumed to be applicable for large watersheds. In our poster we report the results of a study to test the validity of this relationship. Five nested watersheds (2.1 to 19.2 sq. km) were selected in the Adirondack Mountains near Jay, NY (USA). Stage was monitored every 15-minutes using a 1500 mm capacitance rod at the mouth of each watershed. The capacitance rods were installed in stilling wells adjacent to the natural channel. Select storm hydrographs were picked for hydrograph separation during the fall 2003. Preliminary results indicate that the area method is a reasonable predictor of the duration of runoff in these watersheds. Our original intent in pursuing this investigation was to determine how changes in the relationship between drainage area and runoff duration could be attributed to different properties of the watershed. We hypothesized that we would observe a different relationship. The difference could be attributed to differences in our watersheds and the ordinal watersheds from which the relationship was derived. However, in investigating the literature we could find no references that give any information on the original watersheds. This would appear to be a serious handicap for an often-cited method.

  18. 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

  19. 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.

  20. The feasibility of monitoring wilderness lake chemistry with remote sensing methods.

    PubMed

    Vertucci, F A

    1989-04-01

    Wilderness lakes in the U.S. are at risk to the effects of atmospheric pollution. The results of the EPA Western Lake Survey, for example, show that many of the lakes in the West have very low concentrations of dissolved constituents, and are sensitive to acidification. Lakes located in wilderness areas were found to be particularly sensitive: median ANC values of 91.4 μeq/1 compared to 282.7 μeq/1 in non-wilderness areas. Sampling remote wilderness lakes is difficult and expensive. For example, the cost of sampling each lake in the National surface water survey was about $ 4000 per lake. Remote sensing methods may provide an alternative means of monitoring the chemistry of wilderness lakes. This study defines the feasibility of the remote monitoring of lake chemistry in the Adirondack Park region of New York by comparing measured lake chemistry with field reflectance measurements, remote reflectance measurements from aircraft and satellite and laboratory and airborne laser fluorosensor data.Water samples collected from a representative population of Adirondack Park lakes were analyzed for pH, acid neutralizing capacity (ANC), dissolved organic carbon (DOC), total reactive aluminum and plant pigment concentration concurrent with the collection of remote sensing data. Lake parameters estimated from field reflectance measurements which directly effect lake optical properties, total pigments, DOC, and turbidity were estimated with less error and more precision than those parameters not directly related to lake optics, pH, ANC and A1 concentration. Results from airborne MSS and Landsat MSS data produced lower R(2) values than estimates using field reflectance.The concentration of DOC can be estimated remotely by using laser fluorosensing. The spectral-fluorescence properties of DOC were correlated with the pH and aluminum concentrations in the lake water. Remotely measurable DOC fluorescence spectra were used to estimate DOC, H, and A1 concentrations.Of the methods

  1. 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

  2. CASTNet mountain acid deposition monitoring program

    SciTech Connect

    Bowser, J.J.; Anderson, J.B.; Edgerton, E.S.; Mohnen, V.; Baumgardener, R.

    1994-12-31

    Concern over the influence of air pollution on forest decline has led the USEPA to establish the Mountain Acid Deposition Monitoring Program (MADMP) to quantify total deposition at high altitudes, i.e., above cloud base. Clouds can be a major source of atmospheric deposition to sensitive, mountain ecosystems. This program is a part of the Clean Air Status and Trends Network (CASTNet), a national assessment of the effects of the 1990 Clean Air Act. The objectives of MADMP are to estimate total deposition, measure cloud chemistry, and characterize spacial and temporal trends at four selected high altitude sites in the Eastern US. Four MADMP sites have been established for the 1994 field season: Clingman`s Dome, Great Smoky Mountain Nat. Park, TN; Slide Mountain, Catskill State Park, NY; Whiteface Mountain, Adirondack State Park, NY; and Whitetop Mountain, Mt. Rogers Nat`l Recreational Area, VA. An automated cloud collection system will be utilized in combination with continuous measurements of cloud liquid water content in order to estimate cloudwater deposition. Other relevant data will include continuous meteorological measurements, ozone and sulfur dioxide concentrations, wet deposition from rainfall analysis, and dry deposition from filter pack analysis. Quality assurance and quality control measures will be employed to maximize accuracy and precision.

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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.

  8. Alteration Mineralogy of Adirondack-class Rocks in Gusev Crater, Mars

    NASA Astrophysics Data System (ADS)

    Hamilton, V. E.; Ruff, S. W.

    2009-12-01

    The rock Adirondack is the type example of a class of basaltic rocks analyzed by the Mars Exploration Rover Spirit in Gusev crater. Thermal infrared spectra of Adirondack-class rocks acquired by the Mini-TES instrument are distinguishable from spectra of other rock classes by the presence of an emissivity peak at 430 cm-1 and a minimum near 510 cm-1, which are characteristic of olivine. This is the primary spectral class on the plains of Gusev, but spectra of rocks exhibiting similar low wavenumber spectral character have been acquired along the rover traverse in the Columbia Hills, and we have confirmed that these also are Adirondack-class. Linear mixture modeling of their infrared spectra (enabled by applying a correction for dust on the Mini-TES optics) suggests that they are mafic with sulfate minerals present as alteration phases (up to 25%) in the majority of these rocks, broadly consistent with APXS-measured chemistry. The RAT-brushed surface of an unusual plains rock referred to as Mazatzal exhibits a spectral shape and modeled mineralogy consistent with the absence of olivine and the presence of amorphous phases low in silica, and is a coating unlike any other observed on Mars. We have also used a previously-demonstrated factor analysis and target transformation (FATT) technique with Adirondack-class rock spectra to retrieve the spectral shapes of independently-varying components within the data set. Using this approach, we have identified four shapes attributable to two distinct surface components, fine particulate surface dust, and a second dust component similar to downwelling sky radiance and/or dust on the Mini-TES optics. The two surface shapes do not resemble those of the two canonical surface types measured from orbit. One of the surface shapes is very similar to that of the lherzolitic Shergottite ALH A77005. Preliminary linear mixture analysis of this shape shows that it is dominated by olivine (~57%, ~Fo45) and pyroxene (~28%), with minor

  9. Effect of acidification damages on the economic value of the Adirondack fishery to New York anglers

    SciTech Connect

    Mullen, J.K.; Menz, F.C.

    1985-02-01

    A travel cost model is used to estimate losses in the net economic value of the Adirondack recreational fishery resulting from damages caused by acidic deposition. Annual losses to New York resident anglers are estimated to be approximately $1 million per year in 1976 dollars. Although there are many reasons why these damages understate the full extent of losses to both current users and others, this research represents one of the initial attempts to quantify one type of cost associated with the acidic deposition problem.

  10. Episodic acidification and associated fish and benthic invertebrate responses of four adirondack headwater streams. Methods report

    SciTech Connect

    Kretser, W.A.; Simonin, H.A.; Bath, D.W.; Gallagher, J.; Olson, M.L.

    1993-10-01

    Four low order Adirondack streams were investigated from September 1988 through June 1990 to examine the effects of hydrologic events in relation to stream chemistry and associated biological communities. The four streams were monitored continuously for pH, specific conductivity, temperatures, flow and water quality using a variety of instrumentation and procedures. During base flow and hydrologic events, weekly water samples were collected manually. Assessment of the biological communities in response to changes in water chemistry involved a number of standard fisheries techniques including electroshocking for population estimates, in situ bioassay experiments and radio tagging experiments.

  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. Cycling of iron and trace metals in the sediments of acidic lakes

    SciTech Connect

    Gubala, C.P.

    1988-01-01

    This study focused on four lakes receiving acidic deposition located in the Adirondack Park, New York, U.S.A. The biogeochemistry of sediments and interstitial water along a depth transect in Big Moose, Lake was examined by chemical analysis of sediment and pore water. Solid phases of iron, manganese, aluminum, lead and zinc were quantified, using a sequential chemical extraction process. {sup 210}Pb dating, and equilibrium and diffusion transport modeling were used to assess the degree of post-depositional reprocessing of these metals. The sediment chemistry of Dart Lake, Lake Rondaxe and South Lake, were compared to the sediment processes observed in Big Moose Lake to assess inter-lake variability.

  15. 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.

  16. 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.

  17. 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.

  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

    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 1990 s. 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. 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

  20. Lake variability: key factors controlling mercury concentrations in New York State fish.

    PubMed

    Simonin, Howard A; Loukmas, Jefferey J; Skinner, Lawrence C; Roy, Karen M

    2008-07-01

    A 4year study surveyed 131 lakes across New York State beginning in 2003 to improve our understanding of mercury and gather information from previously untested waters. Our study focused on largemouth and smallmouth bass, walleye and yellow perch, common piscivorous fish shown to accumulate high mercury concentrations and species important to local fisheries. Fish from Adirondack and Catskill Forest Preserve lakes generally had higher mercury concentrations than those from lakes in other areas of the state. Variability between nearby individual lakes was observed, and could be due to differences in water chemistry, lake productivity or the abundance of wetlands in the watershed. We found the following factors impact mercury bioaccumulation: fish length, lake pH, specific conductivity, chlorophyll a, mercury concentration in the water, presence of an outlet dam and amount of contiguous wetlands.

  1. 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

  2. The Influence of Speckled Alder on Nitrogen Accumulation in Adirondack Wetlands

    NASA Astrophysics Data System (ADS)

    Kiernan, B. D.; Hurd, T. M.; Raynal, D. J.

    2001-05-01

    Shrub-dominated wetlands of the Adirondacks typically support vigorous populations of nitrogen-fixing speckled alder Alnus incana (L.) Moench var. americana Regel), and are the second most abundant wetland type in the Adirondack region. In symbiotic association with an actinomycete of the genus Frankia, this shrub fixes 37-43 kg N/ha/yr in monotypic stands. This study was undertaken to quantify the abundance of alder in wetlands typed as "Scrub-shrub 1" (SS1; known as alder/willow wetlands) in the National Wetlands Inventory, and to determine the accumulation of nitrate and ammonium in alder wetland substrates. Twenty wetlands from the Oswegatchie-Black (OB) and Upper Hudson (UH) watersheds were randomly selected using the Adirondack Park Agency's GIS data base which includes wetland cover types assigned using remotely sensed data. Wetlands designated as "SS1" (scrub-shrub vegetation) and "SS1/EM1" (scrub-shrub with emergent herbaceous vegetation) were included in the sample. Six wetlands varying in alder abundance were chosen to estimate N accumulation in the substrate, with measurement of dissolved inorganic N in groundwater and ion exchange resin extracts. In the OB watershed, A. incana averaged 30 % of total shrub density in SS1 wetlands and 36 % in SS1/EM1 wetlands. Alder accounted for 49 % of all stems in UH SS1 wetlands, 28 % in the SS1/EM1 wetlands and in total accounted for 35 % of all stems in this study. Nitrate in IER extracts and groundwater was significantly higher in high-density alder wetlands (p < 0.05). Eight of the 20 wetlands included in this study were estimated to have less than 3,000 alder stems/ha, and five were estimated to have greater than 10,000 stems/ha. The other seven wetlands averaged 6,000 stems/ha. At nine sites, foliar N equaled or exceeded estimated atmospheric deposition (~10 kg/ha/yr), and was likely derived from N fixation. We conclude that 50 % of the SS1/EM1 wetlands and at least 75 % of the SS1 wetlands in these watersheds

  3. Rocky Mountain acidification study

    SciTech Connect

    Gibson, J.H.; Galloway, J.N.; Schofield, C.; McFee, W.; Johnson, R.; McCarley, S.; Dise, N.; Herzog, D.

    1983-10-01

    The objectives of this report were to determine the sensitivity of watersheds characteristic of the Rocky Mountain Region and the relationship of watershed sensitivity to geology and soils; to evaluate the extent of current acidification and the potential for increasing acidification with increasing deposition of nitrate and sulfate; to evaluate the results of the preceding in terms of impacts on fish populations; and to develop recommendations for assessment of future trends in both changing water chemistry and impacts on fish populations. Areas selected for study included the Rocky Mountain National Ppark and Yellowstone National Park, exemplifying two different geologic types that are representative of a large portion of the Rocky Mountain region. Rocky Mountain National Park is primarily underlain by granite and Yellowstone National Park by volcanic materials. Sensitivity is primarily determined by bedrock geology and varies inversely with elevation. High-elevation lakes and streams in the central Rocky Mountain region are very sensitive to acidic deposition. With respect to fish populations there is currently no evidence of chronic acidification and thus no apparent impact on fisheries. However, the very low base cation concentration observed in the headwater drainages of Rocky Mountain National Park suggests extreme sensitivity to acidification. Waters in volcanic areas such as Yellowstone National Park are generally of high alkalinity and do not represent potentially sensitive habitats. 109 references, 31 figures, 24 tables.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. Tracing Changes in Carbon Chemistry Caused by an Extreme Mid-Summer Rain Event in a Lake-Stream System in the Colorado Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Miller, M.; McKnight, D.; Alexander, K.

    2006-12-01

    We studied the impact of a sustained high elevation rain event in mid-summer on the biogeochemistry of dissolved organic material (DOM) in an aquatic ecosystem in the Colorado Front Range. In the Green Lakes Valley, an alpine-subalpine catchment, the hydrology is typically defined by two distinct periods: snowmelt and baseflow. Similarly, characterization of DOM by fluorescence spectroscopy and other methods shows that the source and chemical character of the DOM changes with the hydrology. Surface water samples were collected from the outlet of a small alpine lake as well as a stream site downstream of a larger subalpine lake from the initiation of snowmelt through late summer. Beginning on July 7th and ending on July 9th 2006 a continuous low intensity rain event produced approximately 9 cm of precipitation. The rain event increased discharge at the two sites to flow rates that were 2.5 fold greater than those observed during peak snowmelt. The fluorescence characteristics of the DOM as well as the percent fulvic acid contribution to the sample were reset to values similar to those observed during snowmelt at the alpine site but were relatively unaffected at the subalpine site. These results suggest that alpine ecosystems are more sensitive to hydrologic changes than subalpine ecosystems and residence times of the lakes in these systems may play an important role in regulating stream chemistry.

  10. Total Mercury and Methylmercury Dynamics; stream export in an upland forested watershed in the Adirondack region of New York State

    NASA Astrophysics Data System (ADS)

    Carleton, W.; Vidon, P.; Mitchell, M. J.

    2012-12-01

    Although levels of mercury and acid rain deposition have greatly declined in recent years due to legislation controls on industry emissions, their legacy has had a lasting effect on the Adirondack region of New York State. This historical mercury deposition is of concern because of the high chance for methylmercury production and export to occur. The impact of forested uplands on methylmercury export remains poorly understood in relation to other ecosystems. Research indicates that sulfate dynamics play a large role in regulating the production of methylmercury in the presence of inorganic mercury; however the relationship between methylmercury production and nitrate availability at various times of the year is less understood, yet, hypothesized to potentially impact sulfate reduction and ultimately methylmercury production in a variety of ecosystems. In this study, mercury and water quality (including sulfate and nitrate) will be monitored in spring, summer and fall of 2012 at 7 locations in Arbutus Watershed, Adirondacks, NY. Proxies (UV absorbance, Fluorescence indices) for total mercury and methylmercury will be utilized to predict export. The main objectives of this research are to determine the relevance of forested uplands in methylmercury export, as well as gain further understanding of mercury dynamics and associated proxies in relation to nitrate and sulfate availability. Photo courtesy of the Adirondack Ecological Center

  11. 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.

  12. New lakes in the Taklamakan Desert

    NASA Astrophysics Data System (ADS)

    Chen, Jiansheng; Wang, Chi-Yuen; Tan, Hongbing; Rao, Wenbo; Liu, Xiaoyan; Sun, Xiaoxu

    2012-11-01

    At the beginning of this century, some new lakes unexpectedly appeared in the Taklamakan Desert - one of the largest and driest deserts in the world. The origin of the water in the new lakes, however, has been a matter of debate. We test the hypotheses by analyzing water samples collected from the new lakes, the Bosten Lake and the foothills of the mountains that surround the desert. Using the isotopic composition of these waters as tracers, together with data from remote sensing, local weather stations and stream gauges, we infer that the new lakes may originate from increased recharge of groundwater from meltwater in the nearby mountains. We further speculate, supported by first-order simulation of earthquake-induced discharge of groundwater from mountains, that the source of this increased recharge may be related to earthquake-induced discharge of groundwater from nearby Altyn and Kunlun Mountains.

  13. 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.

  14. 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

  15. 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

  16. Christmas Mountains

    Atmospheric Science Data Center

    2013-04-17

    article title:  Christmas Mountains     View Larger ... of New Brunswick. Located above image center are the Christmas Mountains, a region of old-growth forest nestled in a remote ... date:  Mar 8, 2001 Images:  Christmas Mountains location:  Canada ...

  17. 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.

  18. Proglacial lakes: character, behaviour and geological importance

    NASA Astrophysics Data System (ADS)

    Carrivick, Jonathan L.; Tweed, Fiona S.

    2013-10-01

    Proglacial lakes are ubiquitous within the Quaternary record and can provide exceptional breadth and depth of palaeoenvironmental information. Present deglaciation is increasing the number and size of proglacial lakes around the world. This study provides a synthesis of knowledge on proglacial lake character and behaviour and critically evaluates the importance of proglacial lakes from a geological perspective. We show how ‘ice-marginal' or ‘ice-contact' lakes and other distal proglacial lakes can be distinguished from each other by geomorphological, sedimentological, chemical and biological characteristics. The key controls on proglacial lake geomorphology and sedimentology are outlined and discussed. Proglacial lakes can exacerbate mountain glacier and ice sheet margin ablation via mechanical and thermal stresses, but very large lakes can moderate summer air temperatures and relatively retard summer ice ablation. Proglacial lakes interrupt meltwater flux and are very efficient sediment traps. Hydrological routing and consequent geomorphological activity can be radically modified by sudden drainage of proglacial lakes and resultant glacial lake outburst floods; exceptionally large proglacial lake drainages affected global ocean circulation and global climate during the Quaternary. Overall, analyses of proglacial lakes can provide a valuable insight into (i) patterns, character and behaviour of mountain glaciers, ice sheets and glaciations, and (ii) the impacts of past, present and future deglaciation.

  19. Alkali metasomatism in the major gneiss, northwest Adirondacks, New York: open system or closed?

    NASA Astrophysics Data System (ADS)

    Carl, James D.

    1981-09-01

    The thickest clastic unit in the northwest Adirondacks. New York, undergoes gradual transition from amphibolite to granulite facies over a distance of 55 km from Emeryville to Colton. This Precambrian quartz-biotite-oligoclase-K-feldspar gneiss with migmatite characteristics has long been cited as having undergone progressive loss of K, Si, Fe2+, Ba and H2O toward Colton and granulite facies conditions (ENGEL and ENGEL, 1958, 1960a. b). Chemical data obtained from new samples, however, cast doubt upon the interpretation of open system alkali metasomatism. Outcrop to outcrop chemical variation is shown to be of similar magnitude to the chemical variation recorded across the entire gneiss belt. Chemical differences between Emeryville and Colton are not those expected from progressive degranitization by loss of alkali-bearing fluid. Ratios of {K}/{Rb} and Ca-Na K suggest that metamorphism was isochemical on the scale of outcrop. These new data were obtained from mixtures of leucosome and fine-grained paragneiss at each of 7 outcrops. The sampling technique contrasts with that of A.E.J. and C. Engel who analyzed leucosome separately from fine grained (‘least altered’) gneiss.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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 A.; 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.

  6. 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

  7. 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) "Spirit Lake"; (5) "Lake Manawa"; (6)…

  8. 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

  9. 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

  10. Patagonian Lakes, Argentina, South America

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Patagonian Lakes of Argentinas Los Glacieres National Park (50.0S, 73.0W) occupying the foothills of the southern Andes Mountains along the border with Chile, are some of the most scenic in South America. The range is covered by a permanent ice cap and glaciers. Glacier activity frequently reaches into the lake region causing blockage and impounding of the waters until water pressure causes the glacier to crack with a roar that can be heard for miles.

  11. 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.

  12. 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.

  13. Age, field, and petrological relationships of the Hyde School Gneiss, Adirondack lowlands, New York: Criteria for an intrusive igneous origin

    SciTech Connect

    McLelland, J. ); Perham, A. ); Chiarenzelli, J.

    1992-01-01

    Alaskitic and tonalitic rocks constituting Hyde School Gneiss (HSG) occur in 14 domical bodies in the Adirondack lowlands. Recent models have interpreted these bodies as metamorphosed rhyolitic and dacitic ash-flow deposits forming the basal member of a regional stratigraphic package. In contrast, this paper presents criteria and evidence for an intrusive origin for HSG. Field evidence includes intrusion breccias and complex crosscutting relationships involving mafic layers resembling synplutonic dikes. Petrologic constraints supporting an intrusive origin include: (1) the common occurrence of quartz-mesoperthite hypersolvus assemblages; (2) magmatic features in tonalitic, trondhjemitic, and alaskitic facies, (3) local occurrences of orthopyroxene in all facies of HSG; and (4) the development of marginal garnet-sillimanite gneiss with corundum-spinel-garnet-sillimanite assemblages yielding paleotemperatures of 780-810C and interpreted as restite remaining after anatexis of country rock metapelite by intrusions of hypersolvus granitoids. U-Pb zircon ages reported here suggest that the majority of the HSG was intruded at ca. 1230 Ma, contemporaneous with high-grade metamorphic activity in the Adirondacks and elsewhere in the SW sector of the Grenville Province. Geochronological evidence from a leucogranitic rock crosscutting metasediments on Wellesley Island suggest that these metasediments are older than 1416 {plus minus} 5 Ma.

  14. 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.

  15. 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. PMID:26188804

  16. 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.

  17. 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

  18. 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.

  19. Great Salt Lake, Utah, USA

    NASA Technical Reports Server (NTRS)

    1990-01-01

    As seen from space, the Great Salt Lake, Utah, USA (41.5N, 112.5W) appears as two separate bodies of water with a narrow divider in the middle. At the turn of the century, a railroad bridge without culverts, was built across the lake and ever since, the water and salinity levels have been uneqal on either side. Fed by snowmelt from the nearby Wasatch Mountains, the lake in recent years has had record high water levels, threatening to flood the local areas.

  20. Atlas Mountains

    NASA Technical Reports Server (NTRS)

    2002-01-01

    These are the Anti-Atlas Mountains, part of the Atlas Mountain range in southern Morocco, Africa. The region contains some of the world's largest and most diverse mineral resources, most of which are still untouched. This image was acquired by Landsat 7's Enhanced Thematic Mapper plus (ETM+) sensor on June 22, 2001. This is a false-color composite image made using shortwave infrared, infrared, and red wavelengths. Image provided by the USGS EROS Data Center Satellite Systems Branch.

  1. Overview: Ancient Lake Creede

    USGS Publications Warehouse

    Bethke, Philip M.; Hay, Richard L.

    2000-01-01

    Lake Creede was moderately saline closed-basin lake that developed in the 26.9 Ma Creede caldera in the San Juan Mountains in the southwest Colorado. The volcaniclastic sediments deposited within the late Oligocene lake were first described and named as the Creede Formation by Emmons and Larsen (1923). The lake and its sedimentary fill are of interest first as representatives of a caldera-hosted lake in a silicic volcanic terrane, and second because of the likely involvement of lake fluids or related pore waters in the deposition of the 25 Ma silver and base-metal ores of the Creede mining district north of the Creede caldera (Fig. 1), as proposed Bethke and Rye (1979). Much of the material presented in this volume is based on observation of core samples and on downhole geophysical measurements obtained as part of a U.S. Continental Scientific Drilling Program in the moat of the Creede caldera. These core and downhole studies are supplemented by outcrop studies, some initiated in support of the drilling program (Bethke and Lipman, 1987), and by conceptual studies of the evolution of the Creede caldera and its surrounding landscape. Not surprisingly, not all authors agree on all interpretation. Most disagreements are pointed out in this overview chapter, and may present opportunities for future study.

  2. Development of recent chronologies and evaluation of temporal variations in Pb fluxes and sources in lake sediment and peat cores in a remote, highly radiogenic environment, Cairngorm Mountains, Scottish Highlands

    NASA Astrophysics Data System (ADS)

    Farmer, John G.; MacKenzie, Angus B.; Graham, Margaret C.; Macgregor, Kenneth; Kirika, Alexander

    2015-05-01

    The use of stable Pb isotope analyses in conjunction with recent (210Pb and anthropogenic radionuclide) chronologies has become a well-established method for evaluating historical trends in depositional fluxes and sources of atmospherically deposited Pb using archival records in lake sediment or peat cores. Such studies rely upon (i) simple radioactive disequilibrium between unsupported 210Pb and longer-lived members of the 238U decay series and (ii) well-defined values for the isotopic composition of contaminant Pb and indigenous Pb in the study area. However, areas of high natural radioactivity can present challenging environments for such studies, with potential complications arising from more complex disequilibria in the 238U decay series and the occurrence, at local or regional level, of anomalous, ill-defined stable isotope ratios due to the presence of elevated levels of radiogenic Pb. Results are presented here for a study of a sediment core from a freshwater lake, Loch Einich, in the high natural radioactivity area of the Cairngorm Mountains of Scotland. 238U decay series disequilibria revealed recent diagenetic re-deposition of both U and 226Ra, the latter resulting in a requirement to use a modified calculation to derive a 210Pb chronology for the core. Confidence in the chronology was provided by good agreement with the independent 241Am chronology, but the 137Cs distribution was affected by significant post-depositional mobility in the organic-rich sediment. The systematics of variations in 230Th, 232Th and stable Pb isotope ratio distributions were used to establish the indigenous Pb characteristics of the sediment. The relatively high radiogenic content of the indigenous Pb resulted in complications in source apportionment, in particular during the 20th century, with multiple natural and anthropogenic sources precluding the use of a simple binary mixing model. Consequently, 206Pb/207Pb ratios in Scottish moss samples from an archive collection were

  3. Himalayan Mountain Range, India/China

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The frontier between India (Kashmir) and China (Tibet) (33.5N, 79.5E) lies across the narrow land bridge between the two lakes near the center of this photo. Many of the peaks in this region of the Karakoram and Latakh ranges of the Himalayan Mountains, exceed 20,000 ft. making it one of the most remote regions of the Earth. The large end lake is the Kako in China and the long narrow lake is the Pangong in India.

  4. A preliminary synthesis of structural, stratigraphic, and magnetic data from part of the northwest Adirondacks, New York

    USGS Publications Warehouse

    Foose, M.P.; Brown, C. Ervin

    1976-01-01

    Synthesis of recent work in the NW Adirondacks, New York allows the development of a coherent geologic picture. Mapping of the Precambrian rock units enables the recognition of four major units which are, from bottom to top, 1) Granitic Gneiss (alaskite), 2) Lower Marble, 3) Major Gneiss, and 4) Upper Marble. Additionally, lenses of amphibolite and granite occur as intrusives within this succession. These rock units have been complexly deformed by three major folding episodes, and by two distinctly different styles of faulting. The result has been to produce large northeast-southwest trending dome and basin structures. Patterns of magnetic intensity closely parallel distribution of rock units and provide additional information for a structural and stratigraphic synthesis-.

  5. In situ bioassays of brook trout (salvelinus fontinalis) and blacknose dace (rhinichthys atratulus) in adirondack streams affected by episodic acidification

    SciTech Connect

    Simonin, H.A.; Kretser, W.A.; Bath, D.W.; Olson, M.; Gallagher, J.

    1993-01-01

    In situ bioassays were conducted using native Adirondack brook trout and blacknose dace in four headwater streams. Conductivity, pH, temperature, and stage height were monitored continuously, and water samples for laboratory analysis were collected during hydrologic episodes. Fish survived well during baseflow conditions, but during periods of spring snowmelt or large precipitation events, survival was poor. Bioassay fish that had been in the stream 15-24 d survived episodes better than fish that had either not become acclimatized or recovered from handling. Duration of exposure to acidic episodes was critical. Extended periods of poor water quality resulted in fish mortality and may be more important to native populations than short acidic episodes.

  6. 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 A.; 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.

  7. 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...

  8. Magnificent Mountains

    ERIC Educational Resources Information Center

    Anderson, Heather

    2004-01-01

    One way to increase awareness of endangered national heritage is to teach youth the importance of the land through the study of selected works of art. This article describes a lesson, in which students will study the work of Thomas Moran and create a mountain range collage. A short biography of Thomas Moran is included.

  9. 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.

  10. 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

  11. Tipping temperatures within Subglacial Lake Ellsworth, West Antarctica

    NASA Astrophysics Data System (ADS)

    Thoma, Malte; Grosfeld, Klaus; Mayer, Christoph; Smith, Andrew; Woodward, John

    2010-05-01

    One of the most remote and undiscovered regions on Earth are subglacial lakes. More than 275 of these lakes have been identified so far. However, from most lakes little more is known but the location or the lateral extent. Their inaccessibility increases the importance of numerical models to investigate the physical conditions in these environments. During the Southern Summer 2008/09, the British Antarctic Survey (BAS) performed field measurements in the Ellsworth Mountains, West Antarctica to survey Subglacial Lake Ellsworth. We apply a three-dimensional fluid-dynamics lake model on the geometry of this lake. We present results, indicating that Subglacial Lake Ellsworth has a unique temperature profile, constituted by the pressure induced by the ice thickness above as well as the slope of the ice-lake interface and compare this with the previously modelled Subglacial Lakes Vostok and Concordia. While Lake Vostok and Lake Concordia show a clear convective regime, driven by geothermal heating from the lakes bottom for the overall lake, the ice load on Lake Concordia constitutes a regime where the line of maximum water density crosses through the lake. This divides the lake into branches with completely different convective regimes Sensitivity studies for glacial and probable future scenarios, where the ice coverage might thin, are discussed.

  12. 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 mountains. (CMK)

  13. 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.

  14. Lake Eyre

    Atmospheric Science Data Center

    2013-04-16

    ...   View Larger Image Lake Eyre is a large salt lake situated between two deserts in one of Australia's driest regions. ... the effect of sunglint at the nadir camera view angle. Dry, salt encrusted parts of the lake appear bright white or gray. Purple areas have ...

  15. Ground-water conditions in the Lake Powell area, Utah

    USGS Publications Warehouse

    Blanchard, Paul J.

    1986-01-01

    The Lake Powell area comprises about 2,450 square miles in south-central Utah. It is subdivided into three geographical areas by the Colorado and San Juan Rivers. The Henry Mountains area is north of the Colorado River, the Navajo Mountain area is south of the San Juan River, and the third area is between the Colorado and San Juan Rivers.

  16. 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.

  17. Mercury cycling in litter and soil in different forest types in the Adirondack region, New York, USA.

    PubMed

    Demers, Jason D; Driscoll, Charles T; Fahey, Timothy J; Yavitti, Joseph B

    2007-07-01

    The fate of mercury in decomposing leaf litter and soil is key to understanding the biogeochemistry of mercury in forested ecosystems. We quantified mercury dynamics in decomposing leaf litter and measured fluxes and pools of mercury in litterfall, throughfall, and soil in two forest types of the Adirondack region, New York, USA. The mean content of total mercury in leaf litter increased to 134% of its original mass during two years of decomposition. The accumulation pattern was seasonal, with significant increases in mercury mass during the growing season (+4.9% per month). Litterfall dominated mercury fluxes into the soil in the deciduous forest, whereas throughfall dominated fluxes into the coniferous forest. The increase in mercury mass in decomposing deciduous litter during the growing season was greater than could be accounted for by throughfall inputs during the growing season (P < 0.05), suggesting translocation of mercury from the soil to the decomposing deciduous litter. This internal recycling mechanism concentrates mercury in the organic horizons and retards transport through the soil, thereby increasing the residence time of mercury in the forest floor. A mass balance assessment suggests that the ultimate fate of mercury in the landscape depends upon forest type and associated differences in the delivery and incorporation of mercury into the soil. Our results show that incorporation of mercury into decaying leaf litter increases its residence time in the landscape and may further delay the recovery of surface waters, fish, and associated biota following control of mercury emissions to the atmosphere.

  18. 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

  19. 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.

  20. 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. PMID:16592797

  1. 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

  2. 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

  3. U-Pb isochron age and Pb isotope systematics of the Golden Fleece vein - implications for the relationship of mineralization to the Lake City caldera, western San Juan Mountains, Colorado.

    USGS Publications Warehouse

    Hon, K.; Ludwig, K. R.; Simmons, K.R.; Slack, J.F.; Grauch, R.I.

    1985-01-01

    A U/Pb isochron age of 27.5 + or - 0.5 m.y. is determined for the Golden Fleece vein, an age which is identical with the age of the quartz latite lavas that the vein cuts. Within the Lake City area, only the Golden Fleece vein contains pitchblende and Au-Ag tellurides and has Pb isotope ratios that together define it as unique within the area. The 27.5 m.y. age relates this vein to the waning stages of the Uncompahgre caldera (27-29) rather than to the Lake City caldera (23.1 m.y.). -G.J.N.

  4. Mesozoic and early Tertiary paleostructure and sedimentology of central Wasatch Mountains, Uinta Mountains, and Uinta basin

    SciTech Connect

    Picard, M.D.; Bruhn, R.L.; Beck, S.L.

    1983-08-01

    During latest Cretaceous-Eocene time, 5,000 m (16,000 ft) of beds were deposited in central and northeast Utah. In the Late Cretaceous, sediment derived from the Sevier-Laramide thrust belt was transported to the east and southeast. Southerly paleocurrent directions in the base of the Currant Creek Formation (Maestrichtian) raise the possibility that uplift of the Uintas may have begun by then. The thrust belt continued as a major highland during the early Paleocene, and major uplift of the Uintas occurred. By the middle Paleocene there was an extensive lake which regressed during the late Paleocene as uplift of the Uintas continued. Lake Uinta reached its maximum size during the middle Eocene. Lower (early Duchesnean) and upper (Late Duchesnean) conglomeratic intervals record major episodes of uplift in the Uintas during latest Eocene. Structurally, the Wasatch Mountains are part of a marginal foreland fold and thrust belt. In the northern Wasatch Mountains, pre-Late Cretaceous thrust fault plates were folded in part of a large, ramp-anticline that is cored by allochthonous, crystalline basement . Foreland thrust belt structures in the central Wasatch Mountains were folded about the east-trending Uinta axis as the Uinta Mountains formed. Eastward movement on the Hogsback thrust during the Paleocene was transferred onto the adjacent Uinta axis and Uinta Mountains structure, causing about 20 km (12 mi) of sinistral slip in the western Uinta Mountains. A south-dipping fault ramp was located beneath the Uinta Mountains and extended to depths of 15 to 20 km (9 to 12 mi). Oblique-slip on this ramp probably resulted in about 20 km (12 mi) of crustal shortening perpendicular to the trend of the mountains.

  5. 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)

  6. 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)

  7. 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.

  8. 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.

  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. Ouachita Mountains, Oklahoma as seen from STS-58

    NASA Technical Reports Server (NTRS)

    1993-01-01

    In this unusually clear view, the Ouachita Mountains of southeastern Oklahoma are framed on the north by Lake Eufaula on the South Canadian River, and on the south by the Red River. Clouds formed by upslope winds border both the north and south sides of the synclines (in a syncline the rock layers dip toward the center of the structure). Toward the west, densely forested mountains give way to gently rolling, less rocky terrain and a drier climate. The mountains centered on Broken Bow, in the lower right corner of the scene, display abundant timber clearcuts that are being regenerated.

  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

    article title:  Lake Constance, Europe     View ... This Multi-angle Imaging SpectroRadiometer (MISR) image of Lake Constance covers an area measuring 355 kilometers x 287 kilometers, and ... wastewater and fertilizers. This leads to overproduction of algae and aquatic plants, exhaustion of available oxygen, loss of some fish ...

  14. 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.

  15. 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. PMID:25421994

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Acute mountain sickness

    MedlinePlus

    High altitude cerebral edema; Altitude anoxia; Altitude sickness; Mountain sickness; High altitude pulmonary edema ... Acute mountain sickness is caused by reduced air pressure and lower oxygen levels at high altitudes. The faster you ...

  2. 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

  3. 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.

  4. Physical Controls on Carbon Flux from a Temperate Lake During Autumn Cooling

    NASA Astrophysics Data System (ADS)

    Czikowsky, M. J.; Miller, S. D.; Tedford, E. W.; MacIntyre, S.

    2011-12-01

    Seasonally-stratified temperate lakes are a source of carbon dioxide to the atmosphere during autumn overturning as CO2 trapped below the thermocline becomes available to the surface for release to the atmosphere. We made continuous measurements of the vertical profile of pCO2 in a ~600 ha temperate lake (Lake Pleasant, maximum depth ~24 m) in southwestern Adirondack Park, New York from mid-September to mid-October 2010 from a moored pontoon boat. Continuous eddy covariance flux measurements of momentum, sensible and latent heat, and CO2 were made in situ, and the water column thermal structure was measured using thermistor chains. The spatial variability (horizontal and vertical) of pCO2 throughout the lake was characterized periodically using a roving profiling system. At the beginning of the study interval, pCO2 at the pontoon boat varied from 500 ppm at the surface to > 3000 ppm below the thermocline. The vertical profile of pCO2 changed markedly during the campaign due to the effects of wind forcing and evaporation (buoyancy), with nearly uniform, high pCO2 throughout the water column at the end of the campaign (Figure 1). The elevated surface water pCO2 increased CO2 emission to the atmosphere.

  5. 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

  6. Mapping Glacial Lakes on the Tibetan Plateau with Landsat TM/ETM+ Imagery

    NASA Astrophysics Data System (ADS)

    Li, J.; Sheng, Y.

    2009-12-01

    With a pronounced temperature rise of 0.16oC per decade, the Tibetan plateau is one of the world’s most vulnerable areas responding to global change. Glaciers and glacial lakes serve as sensitive indicators to these regional climate and water cycle variations. Recent study shows that glaciers on the plateau have retreated dramatically, leading to the expansion of the existing glacial lakes and the emergence ofnew glacial lakes. The existence of these lakes increases the possibility of outburst floods to the downstream areas during the ice melting season. Mapping and monitoring these glacial lakes will facilitate our understanding of the glacier-related hazards and regional climate changes. However, rigorous field surveys of glacial lake dynamics are prohibitive in high-mountainous areas on the plateau due to their low accessibility. Satellite remote sensing provides an efficient and objective tool to analyze the status and variations of glacial lakes. Theoretically, lakes and other surface open water bodies are readily identified in satellite images owing to their very low reflectance in near-infrared (NIR) channels of Landsat sensors. In the mountain regions where glacial lakes are located, cloud shadows, mountain shadows, melting glaciers or even lakes under different conditions (e.g., ice lakes, salt lakes, turbid lakes) could become disturbing factors and create problems to glacial lake delineation. We use normalized difference water index (NDWI), the normalized ratio index between the green and near infrared spectral bands, to differentiate water bodies from other land features. As lake features are on the relatively flat areas, topographic features such as terrain slope and hill shades derived from digital elevation model (DEM) are also used to remove the shadows from lakes. Based on NDWI and topographic characteristics, We have developed an automated hierarchical method to monitor glacial lakes using Landsat TM/ETM+ imagery. Firstly, lakes are roughly

  7. Principles of lake sedimentology

    SciTech Connect

    Janasson, L.

    1983-01-01

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

  8. Chemical and biological recovery from acid deposition within the Honnedaga Lake watershed, New York, USA.

    PubMed

    Josephson, Daniel C; Robinson, Jason M; Chiotti, Justin; Jirka, Kurt J; Kraft, Clifford E

    2014-07-01

    Honnedaga Lake in the Adirondack region of New York has sustained a heritage brook trout population despite decades of atmospheric acid deposition. Detrimental impacts from acid deposition were observed from 1920 to 1960 with the sequential loss of acid-sensitive fishes, leaving only brook trout extant in the lake. Open-lake trap net catches of brook trout declined for two decades into the late 1970s, when brook trout were considered extirpated from the lake but persisted in tributary refuges. Amendments to the Clean Air Act in 1990 mandated reductions in sulfate and nitrogen oxide emissions. By 2000, brook trout had re-colonized the lake coincident with reductions in surface-water sulfate, nitrate, and inorganic monomeric aluminum. No changes have been observed in surface-water acid-neutralizing capacity (ANC) or calcium concentration. Observed increases in chlorophyll a and decreases in water clarity reflect an increase in phytoplankton abundance. The zooplankton community exhibits low species richness, with a scarcity of acid-sensitive Daphnia and dominance by acid-tolerant copepods. Trap net surveys indicate that relative abundance of adult brook trout population has significantly increased since the 1970s. Brook trout are absent in 65 % of tributaries that are chronically acidified with ANC of <0 μeq/L and toxic aluminum levels (>2 μmol/L). Given the current conditions, a slow recovery of chemistry and biota is expected in Honnedaga Lake and its tributaries. We are exploring the potential to accelerate the recovery of brook trout abundance in Honnedaga Lake through lime applications to chronically and episodically acidified tributaries. PMID:24671614

  9. 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.

  10. 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.

  11. A screening procedure for identifying acid-sensitive lakes from catchment characteristics.

    PubMed

    Berg, N H; Gallegos, A; Dell, T; Frazier, J; Procter, T; Sickman, J; Grant, S; Blett, T; Arbaugh, M

    2005-06-01

    Monitoring of Wilderness lakes for potential acidification requires information on lake sensitivity to acidification. Catchment properties can be used to estimate the acid neutralizing capacity (ANC) of lakes. Conceptual and general linear models were developed to predict the ANC of lakes in high-elevation (> or = 2170 m) Wilderness Areas in California's Sierra Nevada mountains. Catchment-to-lake area ratio, lake perimeter-to-area ratio, bedrock lithology, vegetation cover, and lake headwater location are significant variables explaining ANC. The general linear models were validated against independently collected water chemistry data and were used as part of a first stage screen to identify Wilderness lakes with low ANC. Expanded monitoring of atmospheric deposition is essential for improving the predictability of lake ANC.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. Lake Titicaca, Peru and Bolivia, South America

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Lake Titicaca, high in the Andean Altiplano of South America, is on the border between Peru and Bolivia (15.5S, 70.0W). At an altitude of 12,500 ft, an area of 3,206 sq. mi. and a depth of about 900 ft., it is the world's highest navigable fresh water lake. La Paz, the capital city of Bolivia, may be seen near the center left of the image on the eastern downslope side of the mountains. 3,206 sq mi (8,303 sqkm), 12,

  17. 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)

  18. 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

  19. Lake Powell, SE Utah and NE Arizona, USA

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Glen Canyon National Recreation Area with Lake Powell and Monument Valley in both SE Utah and NE Arizona (36.5N, 110.0W) are well known tourist areas in the southwest. Water from Lake Powell feeds the Colorado River before it rages through the Grand Canyon. The darker green areas indicate the high forested country of Navajo Mountain and Black Mesa in Arizona. Shadows from the many steep sided hills add a near three dimensional effect to the scene.

  20. Patterns of Local Circulation in the Itaipu Lake Area: Numerical Simulations of Lake Breeze.

    NASA Astrophysics Data System (ADS)

    Stivari, Sônia M. S.; de Oliveira, Amauri P.; Karam, Hugo A.; Soares, Jacyra

    2003-01-01

    The lake-breeze circulation in the Itaipu region was investigated numerically using a nonhydrostatic version of the Topographic Vorticity Model. The area of study corresponds to a 100 km × 180 km rectangle, located on the Brazil-Paraguay border, with Itaipu Lake in its center. The characteristics of the lake breeze generated by the numerical experiments were consistent with the observations available in the area. The numerical experiments have shown that the land use effect is important in the spatial distribution of the lake-breeze circulation and that the topography contributes to modulating the breeze intensity, with the daytime valley-mountain circulation intensifying the lake breeze. However, the circulation pattern observed during daytime over the region is mainly due to the Itaipu Lake presence. The numerical results indicated that Itaipu Lake is able to generate and sustain a lake breeze, with 3.5 m s1 of maximum intensity and 1500-m depth, that propagates inland at 5.1 km h1 under typical undisturbed and calm-wind summer conditions.

  1. Fusulinid biostratigraphy of Bird Spring Formation in Spring Mountains near Mountain Springs Pass, Clark County, Nevada

    SciTech Connect

    Gamache, M.T.; Webster, G.D.

    1987-05-01

    Fusulinids from a 955.16 m thick section of Chesterian into Wolfcampian rocks of the Indian Springs and Bird Spring formations exposed near Mountain Springs Pass represent the biozones of Millerella to Pseudoschwagerina. Species of Millerella, Plectofusulina, Staffella, Schubertina, Pseudostaffella, Profusulinella, Fusulinella, Beedeina, Oketaella, Pseudofusulina, Triticites, Schwagerina, Eoparafusulina, and Cuniculinella were described. One new species of Millerella and three new species of Tricities were named. The Mountain Springs section can be correlated intraregionally with other sections in Clark County using similar cherty limestones or sandstone-dominated strata in association with biozones recognized in the southern Great Basin. The thickening of strata from the Mountain Springs section to the Arrow Canyon and Lee Canyon sections demonstrated by this method reflects each section's position to the northeast-trending Las Vegas-Wasatch hinge line between thin, shallow shelf sediments and thicker sediments to the west after palinspastic reconstruction. The large diversity of fusulinid species in the Mountain Springs section relative to Arrow Canyon and Lee Canyon suggests that a fusulinid diversity index may be useful in correlating similar paleoenvironments. Fusulinid biozones of the Mountain Springs section can also be correlated regionally with fusulinid subbiozones A through G of the Shasta Lake area in northern California and with fusulinid biozones of the Mid-Continent based on similar species and occurrences.

  2. 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

  3. 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.

  4. Regional analysis of the effect of paved roads on sodium and chloride in lakes.

    PubMed

    Kelting, Daniel L; Laxson, Corey L; Yerger, Elizabeth C

    2012-05-15

    Salinization of surface water from sodium chloride (road salt) applied to paved roads is a widely recognized environmental concern in the northern hemisphere, yet practical information to improve winter road management to reduce the environmental impacts of this deicer is lacking. The purpose of our study was to provide such information by developing baseline concentrations for sodium and chloride for lakes in watersheds without paved roads, and then determining the relationship between these ions and density, type, and proximity of paved roads to shoreline. We used average summer (June-September) sodium and chloride data for 138 lakes combined in a watershed based analysis of paved road networks in the Adirondack Park of New York, U.S.A. The watersheds used in our study represented a broad range in paved road density and type, 56 of which had no paved roads. Median lake sodium and chloride concentrations in these 56 watersheds averaged 0.55 and 0.24 mg/L, respectively. In contrast, the median sodium and chloride concentrations for the 82 lakes in watersheds with paved roads were 3.60 and 7.22 mg/L, respectively. Paved road density (lane-km/km(2)) was positively correlated with sodium and chloride concentrations, but only state roads were significantly correlated with sodium and chloride while local roads were not. State road density alone explained 84 percent of the variation in both ions. We also successfully modeled the relationship between road proximity to shoreline and sodium and chloride concentrations in lakes, which allowed us to identify sections of road that contributed more to explaining the variation in sodium and chloride in lakes. This model and our approach could be used as part of larger efforts to identify environmentally sensitive areas where alternative winter road management treatments should be applied.

  5. Sulfur constituents and cycling in waters, seston, and sediments of an oligotrophic lake

    SciTech Connect

    David, M.B.; Mitchell, M.J.

    1985-11-01

    Organic and inorganic sulfur constituents in streams, the water column, seston, and sediments of an oligotrophic Adirondack lake were measured for 2 years (1981-1983). Soluble organic S constituents (C-bonded S and water sulfate) were 1-18% of total S in streams, the water column, and lake outlet. Seston S (0.3-1.2% dry mass) in South Lake consisted of ester sulfate (44-59%), C-bonded S (32-43%), sulfate (10-16%), and nonsulfate inorganic S (<2%). Rates of S deposition measured in sediment traps were highest after spring turnover. The organic matter content (52-81% dry mass) of traps at 5, 8, and 15.5 m showed no significant differences. Net mineralization of seston inputs was 26% based on mass balance calculations, with 43% of the ester sulfate input mineralized. Because most of the S input to the sediments was not mineralized, organic S accumulated and constituted the major (74% of total S) S component of the sediment.

  6. 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.

  7. 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.

  8. Geographical ancestry of Lake Malawi's cichlid fish diversity

    PubMed Central

    Genner, Martin J.; Ngatunga, Benjamin P.; Mzighani, Semvua; Smith, Alan; Turner, George F.

    2015-01-01

    The Lake Malawi haplochromine cichlid flock is one of the largest vertebrate adaptive radiations. The geographical source of the radiation has been assumed to be rivers to the south and east of Lake Malawi, where extant representatives of the flock are now present. Here, we provide mitochondrial DNA evidence suggesting the sister taxon to the Lake Malawi radiation is within the Great Ruaha river in Tanzania, north of Lake Malawi. Estimates of the time of divergence between the Lake Malawi flock and this riverine sister taxon range from 2.13 to 6.76 Ma, prior to origins of the current radiation 1.20–4.06 Ma. These results are congruent with evaluations of 2–3.75 Ma fossil material that suggest past faunal connections between Lake Malawi and the Ruaha. We propose that ancestors of the Malawi radiation became isolated within the catchment during Pliocene rifting that formed both Lake Malawi and the Kipengere/Livingstone mountain range, before colonizing rivers to the south and east of the lake region and radiating within the lake basin. Identification of this sister taxon allows tests of whether standing genetic diversity has predisposed Lake Malawi cichlids to rapid speciation and adaptive radiation. PMID:26063752

  9. Geographical ancestry of Lake Malawi's cichlid fish diversity.

    PubMed

    Genner, Martin J; Ngatunga, Benjamin P; Mzighani, Semvua; Smith, Alan; Turner, George F

    2015-06-01

    The Lake Malawi haplochromine cichlid flock is one of the largest vertebrate adaptive radiations. The geographical source of the radiation has been assumed to be rivers to the south and east of Lake Malawi, where extant representatives of the flock are now present. Here, we provide mitochondrial DNA evidence suggesting the sister taxon to the Lake Malawi radiation is within the Great Ruaha river in Tanzania, north of Lake Malawi. Estimates of the time of divergence between the Lake Malawi flock and this riverine sister taxon range from 2.13 to 6.76 Ma, prior to origins of the current radiation 1.20-4.06 Ma. These results are congruent with evaluations of 2-3.75 Ma fossil material that suggest past faunal connections between Lake Malawi and the Ruaha. We propose that ancestors of the Malawi radiation became isolated within the catchment during Pliocene rifting that formed both Lake Malawi and the Kipengere/Livingstone mountain range, before colonizing rivers to the south and east of the lake region and radiating within the lake basin. Identification of this sister taxon allows tests of whether standing genetic diversity has predisposed Lake Malawi cichlids to rapid speciation and adaptive radiation.

  10. 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.

  11. 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.

  12. Four year geochemical analysis of surface waters surrounding Horseshoe Lake and McLeod Lake at Mammoth Lakes, CA

    NASA Astrophysics Data System (ADS)

    Luu, N. C.; Ellis, A. S.

    2013-12-01

    A natural analog to carbon sequestration, Mammoth Mountain and the surrounding area have been researched extensively, spanning over multiple scientific disciplines. Previous and current research endeavors provide further insight into the possible impacts and consequences of geological carbon sequestration. The focus of this study builds upon previous research, with a four year analyses on the varying fluxes that occur within the snowmelt season and the controls it has over the water chemistry within the area surrounding Horseshoe Lake and McLeod Lake. The flux of solute concentrations in both McLeod and Horseshoe Lake are governed by hydrologic processes that are connected to: (1) seasonal snowpack availability; (2) soil coverage; (3) hydrologic flow paths available during snowmelt season; (4) permeability of these flow paths; (5) interaction of snowmelt water and groundwater; and (6) the geology of the area. The purpose of this research is to identify the primary mechanism(s) that control the water chemistry of the local streams, Horseshoe Lake, and McLeod Lake. Preliminary data gathered in 2012 shows that low snowpack availability increases concentrations of ionic constituents in comparison previously collected data by graduate students in 2010-2011. Scatter plots of molar ratios of Mg/Na vs. Ca/Na show strong correlations to silicate weathering while plots of collected samples in 2012 suggests a mixing trend; with McLeod Lake and streams that discharge into Horseshoe Lake as end members. Ionic solute concentrations are relatively higher in streams that discharge into Horseshoe Lake compared to the lake itself. Water samples from Horseshoe Lake have higher alkalinity values in comparison to McLeod Lake (0.091 μg/L and 0.236 μg/L respectively), indicative of enhanced weathering. McLeod Lake solute concentrations appear to be dilute due to significant snowmelt contribution, supplied from nearby talus formations that are highly permeable. Data collected over the

  13. Great Lakes

    USGS Publications Warehouse

    Edsall, Thomas A.; Mac, Michael J.; Opler, Paul A.; Puckett Haecker, Catherine E.; Doran, Peter D.

    1998-01-01

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

  14. Pesticides in mountain yellow-legged frogs (Rana muscosa) from the Sierra Nevada Mountains of California, USA.

    PubMed

    Fellers, Gary M; McConnell, Laura L; Pratt, David; Datta, Seema

    2004-09-01

    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 gamma-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.

  15. 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.

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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 forma