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Sample records for remote mountain lake

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    Highlights: • We quantified pelagic microplastic pollution in Lake Hovsgol, Mongolia. • Lake Hovsgol is more polluted with microplastics than Lakes Huron and Superior. • Microplastics came from consumer goods; no microbeads/few pellets were observed. • Microplastics were sourced from population centers and distributed by the winds. • Without waste management, even small populations can heavily pollute large lakes. - Abstract: 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

  2. AL:PE - Acidification of Mountain Lakes: Palaeolimnology and Ecology. Part 2 - Remote Mountain Lakes as Indicators of Air Pollution and Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Wathne, Bente M; Patrick, Simon; Cameron, Nigel [eds.

    1997-07-01

    AL:PE is a multi-disciplinary and multi-national project coordinated by research groups in London and Oslo. It is funded by the European Commission, The project is described in this report. The project is the first comprehensive study of remote mountain lakes on a European scale. It is concerned with ecosystems in the arctic and alpine regions of Europe that are threatened by acid deposition, toxic air pollutants and climatic change despite their remoteness. The studies are important not only for ecosystems of the lakes, for which they were designed, but for the arctic and alpine regions in general, since the lakes with their sediment records act as environmental sensors. The AL:PE results illustrate two overarching issues: (1) the importance of these remote and sensitive ecosystems as sensors of long-range transported pollutants and as providers of early warning signals for more widespread environmental change; and (2) the importance and urgency of understanding the present and future impact of pollutants, both singly and in combination, on aquatic ecosystems. Currently, acid deposition is considered the most potent threat. In the context of global warming, however, it is a formidable scientific challenge to disentangle the interactions between the effects of changing deposition patterns of acids, nutrients, trace metals and trace organics. The AL:PE programme has begun to address this challenge and its successor EU project, MOLAR, is designed to tackle the issues more more specifically by focusing on in-depth studies of key sites. 97 refs., 192 figs., 100 tabs.

  3. MOLAR. Measuring and modelling the dynamic response of remote mountain lake ecosystems to environmental change: A programme of Mountain Lake Research. MOLAR Project Manual. September 1997

    Energy Technology Data Exchange (ETDEWEB)

    Wathne, Bente M. [ed.; Hansen, Hege E.

    1997-12-31

    MOLAR (Mountain Lake Research) is an extensive European cooperative research project with 23 partners. It is funded within the European Commission Framework Programme IV: Environment and Climate with assistance from INCO. It is coordinated by the Environmental Change Research Centre (ECRE) at University College London and the Norwegian Institute for Water Research (NIVA). This report describes the practical working methods of the project. Preparatory work and methods for sampling in the field are given in detail. Also described are sample handling after field work, where to send the sample material for analysis and how to treat the results. 92 refs., 10 figs., 7 tabs.

  4. Seasonal ecosystem variability in remote mountain lakes: implications for detecting climatic signals in sediment records

    Czech Academy of Sciences Publication Activity Database

    Catalan, J.; Ventura, M.; Brancelj, A.; Granados, I.; Thies, H.; Nickus, U.; Korhola, A.; Lotter, A. F.; Barbieri, A.; Stuchlik, E.; Lien, L.; Bitušík, P.; Buchaca, T.; Camarero, L.; Goudsmit, G. H.; Kopáček, Jiří; Lemcke, G.; Livingstone, D. M.; Müller, B.; Rautio, M.; Šiško, M.; Sorvari, S.; Šporka, F.; Strunecký, O.; Toro, M.

    2002-01-01

    Roč. 28, č. 1 (2002), s. 25-46 ISSN 0921-2728 Grant - others:EC(XE) MOLAR ENV4 CT95 0007; Swiss FOES (XE) 95.0518-1 Keywords : alpine lakes * chlorophyll * thermal regime Subject RIV: DA - Hydrology ; Limnology Impact factor: 1.731, year: 2002

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

    Science.gov (United States)

    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.

  6. MOLAR Progress Report 1/1997. March 1996 - March 1997. Measuring and modelling the dynamic responce of remote mountain lake ecosystems to environmental change: A programme of Mountain Lake Research - MOLAR

    Energy Technology Data Exchange (ETDEWEB)

    Wathne, Bente M [ed.

    1997-07-19

    MOLAR (Mountain Lake Research) is an extensive European cooperative research project with 23 partners. It is funded within the European Commission Framework Programme IV: Environment and Climate with assistance from INCO. It is coordinated by the Environmental Change Research Centre (ECRE) at University College London and the Norwegian Institute for Water Research (NIVA). The project has four major strands, also called Work Packages (WP), and the present report discusses the progress for the first working year of each WP. 19 refs., 1 fig.

  7. The chemical and biological response of two remote mountain lakes in the Southern Central Alps (Italy) to twenty years of changing physical and chemical climate

    OpenAIRE

    Andrea LAMI; Pierluigi CAMMARANO; Michele ARMIRAGLIO; Pierisa PANZANI; Roberta BETTINETTI; Alessandra PUGNETTI; Anna M. NOCENTINI; Gabriele A. TARTARI; Simona MUSAZZI; Giuseppe MORABITO; Angela BOGGERO; Marina MANCA; Michela ROGORA; Rosario MOSELLO; Aldo MARCHETTO

    2004-01-01

    Two small high mountain lakes in the Alps were monitored in 1984-2003 to follow their response to changes in human impact, such as deposition of atmospheric pollutants, fish stocking and climate change. The results were compared to occasional samplings performed in the 1940s, and to the remains found in sediment cores. When monitoring started, the most acid-sensitive of them, Lake Paione Superiore, was acidified, with evident effects in its flora and fauna: benthic diatoms assemblage was shif...

  8. The chemical and biological response of two remote mountain lakes in the Southern Central Alps (Italy to twenty years of changing physical and chemical climate

    Directory of Open Access Journals (Sweden)

    Andrea LAMI

    2004-02-01

    Full Text Available Two small high mountain lakes in the Alps were monitored in 1984-2003 to follow their response to changes in human impact, such as deposition of atmospheric pollutants, fish stocking and climate change. The results were compared to occasional samplings performed in the 1940s, and to the remains found in sediment cores. When monitoring started, the most acid-sensitive of them, Lake Paione Superiore, was acidified, with evident effects in its flora and fauna: benthic diatoms assemblage was shifted towards acidophilous species, and zooplankton lost the dominant species, Arctodiaptomus alpinus. Palaeolimnological studies outlined that lake acidification paralleled the increasing input of long-range transported industrial pollutants, traced by spherical carbonaceous particles. On the contrary, the biota of Lake Paione Inferiore appeared to be mainly affected by fish stocking. In the last twenty years, decrease in acid load from the atmosphere led to an improvement in lake water quality, with an increase in both pH and alkalinity. First signs of biological recovery were identified, such as change in diatom flora and appearance of sensitive species among benthic insects. However, climate change and episodic deposition of Saharan dust were important driving factors controlling lake water chemistry. Further monitoring to assess the effects of climate change and of the increasing load of nitrogen and other pollutants is recommended.

  9. Age dependence of the accumulation of organochlorine pollutants in brown trout (Salmo trutta) from a remote high mountain lake (Redo, Pyrenees)

    International Nuclear Information System (INIS)

    Vives, I.; Grimalt, J.O.; Ventura, M.; Catalan, J.; Rosseland, B.O.

    2005-01-01

    Polychlorobiphenyls (PCBs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and DDT were examined in the muscle of brown trout (Salmo trutta) from a high mountain lake located in the Pyrenees (Catalonia, Spain) that was used as a model of these lacustrine environments. Results indicate that fish age is the main factor of variability among specimens in this population that is subjected to atmospheric inputs of the organochlorine compounds (OC). Increases of 2- and 20-fold between fish aged 1 year and 15 years old are found. The observed pattern cannot be explained in terms of fish size, condition factor, or muscle lipid content. Higher molecular weight compounds (higher lipophilicity) are better correlated with fish age than low molecular weight compounds. A transformation from 4,4'-DDT to 4,4'-DDE occurs in fish after ingestion; this results in amplified age-dependent signals, especially in male specimens. In contrast, PCB congener no. 180 has lower age dependence than the general OC group, which could be due to its high hydrophobicity (log K ow > 7). In any case, selective accumulation of hydrophobic compounds is already observed among younger fish (age, 1 year). Due to this effect, the relative OC composition does not reflect the main OC pollutants in the lake waters. - Trout in high mountain lakes display age-dependent accumulation of certain organochlorine pollutants

  10. Age dependence of the accumulation of organochlorine pollutants in brown trout (Salmo trutta) from a remote high mountain lake (Redo, Pyrenees)

    Energy Technology Data Exchange (ETDEWEB)

    Vives, I. [Department of Environmental Chemistry, Institute of Chemical and Environmental Research (CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain); Grimalt, J.O. [Department of Environmental Chemistry, Institute of Chemical and Environmental Research (CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain)]. E-mail: jgoqam@cid.csic.es; Ventura, M. [Limnology Group (CSIC-UB), Centre for Advanced Studies of Blanes (CEAB-CSIC), Acces Cala St. Francesc, 14, Blanes 17300, Catalonia (Spain); Catalan, J. [Limnology Group (CSIC-UB), Centre for Advanced Studies of Blanes (CEAB-CSIC), Acces Cala St. Francesc, 14, Blanes 17300, Catalonia (Spain); Rosseland, B.O. [Norwegian Institute for Water Research (NIVA), P.O.B. 173 Kjelsaas, N-0411 Oslo (Norway); Institute for Biology and Nature Conservation, The Agricultural University of Norway (NLH) (Norway)

    2005-01-01

    Polychlorobiphenyls (PCBs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and DDT were examined in the muscle of brown trout (Salmo trutta) from a high mountain lake located in the Pyrenees (Catalonia, Spain) that was used as a model of these lacustrine environments. Results indicate that fish age is the main factor of variability among specimens in this population that is subjected to atmospheric inputs of the organochlorine compounds (OC). Increases of 2- and 20-fold between fish aged 1 year and 15 years old are found. The observed pattern cannot be explained in terms of fish size, condition factor, or muscle lipid content. Higher molecular weight compounds (higher lipophilicity) are better correlated with fish age than low molecular weight compounds. A transformation from 4,4'-DDT to 4,4'-DDE occurs in fish after ingestion; this results in amplified age-dependent signals, especially in male specimens. In contrast, PCB congener no. 180 has lower age dependence than the general OC group, which could be due to its high hydrophobicity (log K{sub ow} > 7). In any case, selective accumulation of hydrophobic compounds is already observed among younger fish (age, 1 year). Due to this effect, the relative OC composition does not reflect the main OC pollutants in the lake waters. - Trout in high mountain lakes display age-dependent accumulation of certain organochlorine pollutants.

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

    Science.gov (United States)

    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.

  12. [Decompression problems in diving in mountain lakes].

    Science.gov (United States)

    Bühlmann, A A

    1989-08-01

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

  13. Measured and modelled trends in European mountain lakes: results of fifteen years of cooperative studies

    Directory of Open Access Journals (Sweden)

    Michela ROGORA

    2004-02-01

    Full Text Available Papers included in this Special Issue of the Journal of Limnology present results of long-term ecological research on mountain lakes throughout Europe. Most of these studies were performed over the last 15 years in the framework of some EU-funded projects, namely AL:PE 1 and 2, MOLAR and EMERGE. These projects together considered a high number of remote lakes in different areas or lake districts in Europe. Central to the projects was the idea that mountain lakes, while subject to the same chemical and biological processes controlling lowland lakes, are more sensitive to any input from their surroundings and can be used as earlywarning indicators of atmospheric pollution and climate change. A first section of this special issue deal with the results of long-term monitoring programmes at selected key-sites. A second section focuse on site-specific and regional applications of an acidification model designed to reconstruct and predict long-term changes in the chemistry of mountain lakes.

  14. Perspectives for an integrated understanding of tropical and temperate high-mountain lakes

    Directory of Open Access Journals (Sweden)

    Jordi Catalan

    2016-03-01

    , high-mountain lake systems are excellent model ecosystems for applying an investigation linking airshed to sediments functional views. Additionally, the study of the mountain lakes districts as functional metacommunity units may reveal key differences in the distribution of organisms of limited (slow dispersal. We propose that limnological studies at tropical and temperate high mountain lakes should adhere to a common general paradigm. In which biogeochemical processes are framed by the airshed-to-sediment continuum concept and the biogeographical processes in the functional lake district concept. The solid understanding of the fundamental limnological processes will facilitate stronger contributions to the assessment of the impacts of the on-going global change in remote areas.

  15. Investigations on pelagic food webs in mountain lakes - aims and methods

    Directory of Open Access Journals (Sweden)

    Jirí NEDOMA

    1999-08-01

    Full Text Available A methodical approach for the assessment of pelagic biomass and the main carbon fluxes in remote and hardly accessible mountain lakes was elaborated and tested. Number and biomass of bacteria (BAC, autotrophic picoplankton (APP, heterotrophic nanoflagellates (HNF, ciliates (CIL, phytoplankton (PHY, zooplankton smaller than 40 μm (ZOOS and zooplankton larger than 40 μm (ZOOL were investigated regularly during two ice-free periods in 13 European mountain lakes (1st level approach – fixed samples elaborated in specialized laboratories. Carbon fluxes measured in 9 lakes included: primary production, exudation by PHY and BAC uptake of exudates, BAC production, elimination of BAC. These processes were measured in the field by specialized teams (2nd level approach. The ranges of values found in mountain lakes were evaluated and possible methodical and interpretative errors discussed. BAC were a significant component of pelagic biomass. The intercomparison between different partners showed differences in bacterial counts lower than 10%, whereas the mean cell volumes measured fluctuated by more than 40%. APP was never found in a significant quantity, except in one lake. HNF and CIL, though regularly found, were usually scarce and only occasionally significant in terms of biomass. The main components of pelagic biomass were BAC, PHY and ZOOL+ZOOS, except for acidified lakes, where zooplankton was very low. In oligotrophic mountain lakes, the percentage of extracellular production in the total primary production was considerable. Bacterial abundance and production often reached values quite comparable with the situation found in lowland mesotrophic lakes during winter.

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

    Science.gov (United States)

    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.

  17. Isotopic composition of dissolved inorganic nitrogen in high mountain lakes: variation with altitude in the Pyrenees

    Science.gov (United States)

    Bartrons, M.; Camarero, L.; Catalan, J.

    2010-05-01

    Nitrogen deposition in remote areas has increased, but the effect on ecosystems is still poorly understood. For aquatic systems, knowledge of the main processes driving the observed variation is limited, as is knowledge of how changes in nitrogen supply affect lake biogeochemical and food web processes. Differences in dissolved inorganic nitrogen (DIN) between lakes cannot be understood without considering catchment characteristics. In mountains, catchment features (e.g., thermal conditions, land cover) vary considerably with elevation. The isotopic composition of nitrogen (δ15N) is increasingly used to study aquatic ecosystem dynamics. Here we explore the variability of δ15N in DIN in high mountain lakes and show that environmental conditions that change with altitude can affect the isotopic ratio. We measured ammonium and nitrate δ15N values in atmospheric deposition, epilimnetic water, deep chlorophyll maximum water (DCMW) and sediment pore water (SPW) from eight mountain lakes in the Pyrenees, both above and below the treeline. Lakes showed relatively uniform δ15N-NH4+ values in SPW (2.2±1.6‰), with no variation corresponding to catchment or lake characteristics. We suggest that organic matter diagenesis under similar sediment conditions is responsible for the low variation between the lakes. In the water column, the range of δ15N values was larger for ammonium (-9.4‰ to 7.4‰) than for nitrate (-11.4‰ to -3.4‰), as a result of higher variation both between and within lakes (epilimnetic vs. DCM water). For both compounds part of the difference correlated with altitude or catchment features (e.g., scree proportion). Based on concentration, chemical and isotopic tendencies, we suggest that patterns arise from the distinct relative contributions of two types of water flow paths to the lakes: one from snowpack melting, with little soil interaction; and another highly influenced by soil conditions. The snow-type flow path contributes low DIN

  18. Carbonaceous particle record in lake sediments from the Arctic and other remote areas of the northern hemisphere

    International Nuclear Information System (INIS)

    Rose, N.L.

    1995-01-01

    Lake sediments, including spheroidal carbonaceous particles produced by high temperature combustion of fossil fuels, contain a record of lake, catchment and atmospheric deposition history. The spatial and temporal distributions of these particles can indicate the extent to which a single lake or a region has been contaminated by airborne pollutants (e.g. sulfur, polycyclic aromatic hydrocarbons (PAHs)) derived from fossil fuels. The carbonaceous particle records of two Arctic lakes, Shuonijavr and Stepanovichjarvi, close to local pollution sources on the Kola Peninsula, Russia, are compared with the record of a remote lake on Svalbard and with mid-latitude remote mountain lakes in Europe and Asia. Although, Shuonijavr and Stepanovichjarvi show relatively high levels of contamination, as expected, the presence of carbonaceous particles at all of the remote sites studied suggests there is a hemispherical background of these particles. Other less remote mountain lakes in Europe have been found to contain significant concentrations of particles and these may represent regional deposition patterns. Carbonaceous particle analysis may provide an effective assessment of whether a lake site is receiving local, regional or background levels of deposition

  19. Persistent toxic substances in remote lake and coastal sediments from Svalbard, Norwegian Arctic: Levels, sources and fluxes

    International Nuclear Information System (INIS)

    Jiao Liping; Zheng, Gene J.; Minh, Tu Binh; Richardson, Bruce; Chen Liqi; Zhang Yuanhui; Yeung, Leo W.; Lam, James C.W.; Yan, Xulin; Lam, Paul K.S.; Wong, Ming H.

    2009-01-01

    Surface sediments from remote lakes and coastal areas from Ny-Alesund, Svalbard, Norwegian Arctic were analyzed for polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). Relatively high levels of PAHs were encountered from several lakes from Ny-Alesund, which were within the range of levels reported for European high mountain lakes and some urban/industrialized areas in the world, pointing to the role of remote Arctic lakes as potential reservoir of semi-volatile organic compounds. Specific patterns of PBDEs were observed, showing higher concentrations of lower brominated compounds such as BDE-7, 17 and 28. Estimated surface sediment fluxes of PAHs in Ny-Alesund remote lakes were similar to those observed for some European high mountain lakes. The current PAH levels in sediments from three lakes exceeded Canadian sediment quality guidelines, suggesting the presence of possible risks for aquatic organisms and the need for further studies. - High levels of PAHs and specific patterns of PBDEs were found in sediments from the remote Norwegian Arctic lakes

  20. Solar and atmospheric forcing on mountain lakes.

    Science.gov (United States)

    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. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Organochlorine compounds in soils and sediments of the mountain Andean Lakes

    International Nuclear Information System (INIS)

    Borghini, Francesca; Grimalt, Joan O.; Sanchez-Hernandez, Juan C.; Barra, Ricardo; Garcia, Carlos J. Torres; Focardi, Silvano

    2005-01-01

    Semi-volatile organochlorine compounds (OC) were analyzed in remote Andean soils and lake sediments. The sampling sites covered a wide latitudinal gradient from 18 deg. S to 46 deg. S along Chile and an altitudinal gradient (10-4500 m). The concentrations were in the order of background levels, involving absence of major pollution sources in the high mountain areas. Significant correlations were found between log-transformed concentrations of hexachlorobenzene, α- and γ-hexachlorocyclohexane in soils and total organic content (TOC). In addition, TOC-normalized concentrations of the most volatile OC showed a significant linear dependence with air temperature. This good agreement points to temperature as a significant factor for the retention of long range transported OC in remote ecosystems such as the Andean mountains, although other variables should not be totally excluded. The highest concentrations of OCs were achieved in the sites located at highest altitude and lowest temperature of the dataset. - Distribution of persistent organochlorine compounds in the Andean Mountain lakes is influenced by temperature

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

    Science.gov (United States)

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

    2012-11-01

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

  3. Remote assessment of reserve capacity of outburst alpine lakes

    Directory of Open Access Journals (Sweden)

    V. G. Konovalov

    2016-01-01

    Full Text Available Results of distant satellite sounding (the TERRA satellite of high-mountainous areas and digital models SRTM 4.1 and ASTER DEM G2 of the same relief were used to calculate the following parameters of high-mountain dammed glacial lakes: area, depth, the water volume, excess of the dam above the water level. It is important for estimation of the water volume that can be dangerous for a break-through of a dammed lake. Formulas deduced to calculate the depth and volume of a lake for several sections of its area were tested and proposed. It is demonstrated that the regression equation V = Hmax × F, where Hmax is maximum depth of the lake, can be used as the parameterization of the formula «lake volume V equals the product of the area F on average depth D». More precise values of the coefficients a and b in the formula V = aFb were also obtained. Parameters and the water volumes of lakes were estimated for the river Gunt (right tributary of Pyanj River basin. According to [28], there are 428 high-mountain lakes in this region with their total area ≥ 2500 m2. For basin Inflow of melted snow and glacier water caused by the rise of mean summer air temperatures in 1931–2015 was estimated for the lake Rivankul basin (the Pamir Mountains.

  4. Biomass and species structure of the phytoplankton of an high mountain lake (Lake Paione Superiore, Central Alps, Italy

    Directory of Open Access Journals (Sweden)

    Roberta BETTINETTI

    1999-08-01

    Full Text Available In the framework of the EU MOLAR Project on “Measuring and modelling the dynamic response of remote mountain lake ecosystems to environmental change” a three whole-year study (1996-1998 on the composition and dynamics of phytoplankton community of the high mountain lake, acid sensitive Lago Paione Superiore (LPS was carried out. The data were analyzed and compared with those gathered during the years 1991-1993. The phytoplankton was made up by nanoplanktonic unicellular algae, the only exception being the colonial Dinobryon sertularia. Just four species, belonging to Chrysophyceae (Chromulina sp., Dinobryon sertularia and Mallomonas alveolata and to Dinophyceae (Gymnodinium sp. were important as biomass and density, and they were always present throughout the year. The prevalence of potentially mixotrophic species suggests an adaptive strategy to the low environmental concentrations of inorganic carbon and phosphorus. The seasonal variations of the total biomass were similar to those observed in the previous years. The total number of species has increased; this could be related with the recent increase of the pH and of the alkalinity.

  5. Combining lake and watershed characteristics with Landsat TM data for remote estimation of regional lake clarity

    Science.gov (United States)

    McCullough, Ian M.; Loftin, Cyndy; Sader, Steven A.

    2012-01-01

    Water clarity is a reliable indicator of lake productivity and an ideal metric of regional water quality. Clarity is an indicator of other water quality variables including chlorophyll-a, total phosphorus and trophic status; however, unlike these metrics, clarity can be accurately and efficiently estimated remotely on a regional scale. Remote sensing is useful in regions containing a large number of lakes that are cost prohibitive to monitor regularly using traditional field methods. Field-assessed lakes generally are easily accessible and may represent a spatially irregular, non-random sample of a region. We developed a remote monitoring program for Maine lakes >8 ha (1511 lakes) to supplement existing field monitoring programs. We combined Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) brightness values for TM bands 1 (blue) and 3 (red) to estimate water clarity (secchi disk depth) during 1990–2010. Although similar procedures have been applied to Minnesota and Wisconsin lakes, neither state incorporates physical lake variables or watershed characteristics that potentially affect clarity into their models. Average lake depth consistently improved model fitness, and the proportion of wetland area in lake watersheds also explained variability in clarity in some cases. Nine regression models predicted water clarity (R2 = 0.69–0.90) during 1990–2010, with separate models for eastern (TM path 11; four models) and western Maine (TM path 12; five models that captured differences in topography and landscape disturbance. Average absolute difference between model-estimated and observed secchi depth ranged 0.65–1.03 m. Eutrophic and mesotrophic lakes consistently were estimated more accurately than oligotrophic lakes. Our results show that TM bands 1 and 3 can be used to estimate regional lake water clarity outside the Great Lakes Region and that the accuracy of estimates is improved with additional model variables that reflect

  6. Isotopic composition of dissolved inorganic nitrogen in high mountain lakes: variation with altitude in the Pyrenees

    Directory of Open Access Journals (Sweden)

    M. Bartrons

    2010-05-01

    Full Text Available Nitrogen deposition in remote areas has increased, but the effect on ecosystems is still poorly understood. For aquatic systems, knowledge of the main processes driving the observed variation is limited, as is knowledge of how changes in nitrogen supply affect lake biogeochemical and food web processes. Differences in dissolved inorganic nitrogen (DIN between lakes cannot be understood without considering catchment characteristics. In mountains, catchment features (e.g., thermal conditions, land cover vary considerably with elevation. The isotopic composition of nitrogen (δ15N is increasingly used to study aquatic ecosystem dynamics. Here we explore the variability of δ15N in DIN in high mountain lakes and show that environmental conditions that change with altitude can affect the isotopic ratio.

    We measured ammonium and nitrate δ15N values in atmospheric deposition, epilimnetic water, deep chlorophyll maximum water (DCMW and sediment pore water (SPW from eight mountain lakes in the Pyrenees, both above and below the treeline. Lakes showed relatively uniform δ15N-NH4+ values in SPW (2.2±1.6‰, with no variation corresponding to catchment or lake characteristics. We suggest that organic matter diagenesis under similar sediment conditions is responsible for the low variation between the lakes.

    In the water column, the range of δ15N values was larger for ammonium (−9.4‰ to 7.4‰ than for nitrate (−11.4‰ to −3.4‰, as a result of higher variation both between and within lakes (epilimnetic vs. DCM water. For both compounds part of the difference correlated with altitude or catchment features (e.g., scree proportion. Based on concentration, chemical and isotopic tendencies, we suggest that patterns arise from the distinct relative contributions of two types of water flow paths to the lakes: one from snowpack melting, with little soil

  7. Global Scale Remote Sensing Monitoring of Endorheic Lake Systems

    Science.gov (United States)

    Scuderi, L. A.

    2010-12-01

    Semi-arid regions of the world contain thousands of endorheic lakes in large shallow basins. Due to their generally remote locations few are continuously monitored. Documentation of recent variability is essential to assessing how endorheic lakes respond to short-term meteorological conditions and longer-term decadal-scale climatic variability and is critical in determining future disturbance of hydrological regimes with respect to predicted warming and drying in the mid-latitudes. Short- and long-term departures from climatic averages, rapid environmental shifts and increased population pressures may result in significant fluctuations in the hydrologic budgets of these lakes and adversely impact endorheic lake/basin ecosystems. Information on flooding variability is also critical in estimating changes in P/E balances and on the production of exposed and easily deflated surfaces that may impact dust loading locally and regionally. In order to provide information on how these lakes respond we need to understand how entire systems respond hydrologically to different climatic inputs. This requires monitoring and analysis of regional to continental-scale systems. To date, this level of monitoring has not been achieved in an operational system. In order to assess the possibility of creating a global-scale lake inundation database we analyzed two contrasting lake systems in western North America (Mexico and New Mexico, USA) and China (Inner Mongolia). We asked two major questions: 1) is it possible to quickly and accurately quantify current lake inundation events in near real time using remote sensing? and, 2) is it possible to differentiate variable meteorological sources and resultant lake inundation responses using this type of database? With respect to these results we outline an automated lake monitoring approach using MODIS data and real-time processing systems that may provide future global monitoring capabilities.

  8. Excess unsupported sup(210)Pb in lake sediment from Rocky Mountain lakes

    International Nuclear Information System (INIS)

    Norton, S.A.; Hess, C.T.; Blake, G.M.; Morrison, M.L.; Baron, J.

    1985-01-01

    Sediment cores from four high-altitude (approximately 3200 m) lakes in Rocky Mountain National Park, Colorado, were dated by sup(210)Pb chronology. Background (supported) sup(210)Pb activities for the four cores range from 0.26 to 0.93 Beq/g dry weight, high for typical oligotrophic lakes. Integrated unsupported sup(210)Pb ranges from 0.81 (a typical value for most lakes) to 11.0 Beq/cmsup(2). The sup(210)Pb activity in the surface sediments ranges from 1.48 to 22.2 Beq/g dry weight. Sedimentation from Lake Louise, the most unusual of the four, has 22.2 Beq/g dry weight at the sediment surface, an integrated unsupported sup(210)Pb=11.0 Beq/cmsup(2), and supported sup(210)Pb=0.74 Beq/g dry weight. sup(226)Ra content of the sediment is insufficient to explain either the high unsupported sup(210)Pb or the sup(222)Rn content of the water column of Lake Louise, which averaged 96.2 Beq/L. We concluded that sup(222)Rn-rich groundwater entering the lake is the source of the high sup(222)Rn in the water column. This, in turn, is capable of supporting the unusually high sup(210)Pb flux to the sediment surface. Groundwater with high sup(222)Rn may control the sup(210)Pb budget of lakes where sediment cores have integrated unsupported sup(210)Pb greater than 2 Beq/cmsup(2)

  9. Quantitative interpretation of great lakes remote sensing data

    International Nuclear Information System (INIS)

    Shook, D.F.; Salzman, J.; Svehla, R.A.; Gedney, R.T.

    1980-01-01

    Remote sensing has been applied in the past to the surveillance of Great Lakes water quality, but it has been only partially successful because of the completely empirical approach taken in relating the multispectral scanning data at visible and near-infrared wavelengths to water parameters. Any remote sensing approach using water color information must take into account (1) the existence of many different organic and inorganic species throughtout the Greak Lakes, (2) the occurrence of a mixture of species in most locations, and (3) spatial (inter- and interlake as well as vertical) variations in types and concentrations of species. The radiative transfer model provides a potential method for an orderly analysis of remote sensing data and a physical basis for developing quantitative algorithms. Predictions and field measurements of volume reflectances are presented which clearly show the advantage of using a radiative transfer model. Spectral absorptance and backscattering coefficients for two inorganic sediments are reported

  10. Remote sensing reflectance of Pomeranian lakes and the Baltic

    Directory of Open Access Journals (Sweden)

    Dariusz Ficek

    2011-11-01

    Full Text Available The remote sensing reflectance Rrs, concentrations of chlorophyll a and other pigments Ci, suspended particulate matter concentrations CSPM and coloured dissolved organic matter absorption coefficient aCDOM(λ were measured in the euphotic zones of 15 Pomeranian lakes in 2007-2010. On the basis of 235 sets of data points obtained from simultaneous estimates of these quantities, we classified the lake waters into three types. The first one, with the lowest aCDOM(440 nm (usually between 0.1 and 1.3 m-1 and chlorophyll a concentrations 1.3 10 m-1, up to 17.4 m-1 in Lake Pyszne; it has a relatively low reflectance (Rrs 4 mg m-3, up to 336 mg m-3 in Lake Gardno. The remote sensing reflectance spectra in these waters always exhibit three peaks (Rrs > 0.005 sr-1: a broad one at 560-580 nm, a smaller one at ca 650 nm and a well-pronounced one at 690-720 nm. These Rrs(λ peaks correspond to the relatively low absorption of light by the various optically active components of the lake water and the considerable scattering (over the entire spectral range investigated due to the high SPM concentrations there. The remote sensing maximum at λ ≈ 690-720 nm is higher still as a result of the natural fluorescence of chlorophyll a. Empirical relationships between the spectral reflectance band ratios at selected wavelengths and the various optically active components for these lake waters are also established: for example, the chlorophyll a concentration in surface water layer Ca = 6.432 e4.556X, where X = [max Rrs (695 ≤ λ ≤ 720 - Rrs(λ = 670] / max Rrs (695 ≤ λ ≤ 720, and the coefficient of determination R2 = 0.95.

  11. UV absorption reveals mycosporine-like amino acids (MAAs in Tatra mountain lake phytoplankton

    Directory of Open Access Journals (Sweden)

    Jerzy Dera

    2013-08-01

    Full Text Available Enhanced absorption of UV radiation, an effect characteristic of mycosporine-like amino acids (MAAs, is reported in samples of phytoplankton from six lakes in the Tatra Mountains National Park (Poland. It was demonstrated that the mass-specific UV absorption coefficients for the phytoplankton in these lakes increased with altitude above sea level. Based on a comparison with the phytoplankton of Alpine lakes, investigated earlier by other authors (cited in this paper, it may be inferred that the phytoplankton of Tatra mountain lakes produce MAAs, which protect plant cells from UV light, the intensity of which increases with altitude.

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

    Science.gov (United States)

    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

  13. Glacial lake outburst flood risk assessment using combined approaches of remote sensing, GIS and dam break modelling

    Directory of Open Access Journals (Sweden)

    Arpit Aggarwal

    2016-01-01

    Full Text Available A great number of glacial lakes have appeared in many mountain regions across the world during the last half-century due to receding of glaciers and global warming. In the present study, glacial lake outburst flood (GLOF risk assessment has been carried out in the Teesta river basin located in the Sikkim state of India. First, the study focuses on accurate mapping of the glaciers and glacial lakes using multispectral satellite images of Landsat and Indian Remote Sensing satellites. For glacier mapping, normalized difference snow index (NDSI image and slope map of the area have been utilized. NDSI approach can identify glaciers covered with clean snow but debris-covered glaciers cannot be mapped using NDSI method alone. For the present study, slope map has been utilized along with the NDSI approach to delineate glaciers manually. Glacial lakes have been mapped by supervised maximum likelihood classification and normalized difference water index followed by manual editing afterwards using Google Earth images. Second, the first proper inventory of glacial lakes for Teesta basin has been compiled containing information of 143 glacial lakes. Third, analysis of these lakes has been carried out for identification of potentially dangerous lakes. Vulnerable lakes have been identified on the basis of parameters like surface area, position with respect to parent glacier, growth since 2009, slope, distance from the outlet of the basin, presence of supraglacial lakes, presence of other lakes in downstream, condition of moraine, condition of the terrain around them, etc. From these criterions, in total, 18 lakes have been identified as potentially dangerous glacial lakes. Out of these 18 lakes, further analysis has been carried out for the identification of the most vulnerable lake. Lake 140 comes out to be the most vulnerable for a GLOF event. Lastly, for this potentially dangerous lake, different dam break parameters have been generated using satellite data

  14. 77 FR 75186 - Notice of Closure, Target Shooting Public Safety Closure on the Lake Mountains in Utah County, UT

    Science.gov (United States)

    2012-12-19

    ... Land Management, Department of the Interior. ACTION: Notice of Closure. SUMMARY: The Bureau of Land... impacts is completed through the land use planning process. The Lake Mountains are a small mountain range... ridge. There are private residences along the lake shore. Utah Lake is a popular area for recreationists...

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

    Science.gov (United States)

    2013-11-19

    ... DEPARTMENT OF AGRICULTURE Forest Service Lake Tahoe Basin Management Unit, California, Heavenly Mountain Resort Epic Discovery Project AGENCY: Lake Tahoe Basin Management Unit, Forest Service, USDA...: The Epic Discovery Project is intended to enhance summer activities in response to the USDA Forest...

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

    Czech Academy of Sciences Publication Activity Database

    Emmer, Adam; Merkl, S.; Mergili, M.

    2015-01-01

    Roč. 246, oct (2015), s. 602-616 ISSN 0169-555X Institutional support: RVO:67179843 Keywords : lake development * geoenvironmental change * GLOF * high-mountain lakes * susceptibility analysis Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 2.813, year: 2015

  17. Conifer density within lake catchments predicts fish mercury concentrations in remote subalpine lakes

    Science.gov (United States)

    Eagles-Smith, Collin A.; Herring, Garth; Johnson, Branden L.; Graw, Rick

    2016-01-01

    Remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited mercury through freshwater food webs, as well as for evaluating the relative importance of mercury loading versus landscape influences on mercury bioaccumulation. The increase in mercury deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in mercury emissions may propagate to changes in Hg bioaccumulation and ecological risk. We evaluated mercury concentrations in resident fish from 28 high-elevation, sub-alpine lakes in the Pacific Northwest region of the United States. Fish total mercury (THg) concentrations ranged from 4 to 438 ng/g wet weight, with a geometric mean concentration (±standard error) of 43 ± 2 ng/g ww. Fish THg concentrations were negatively correlated with relative condition factor, indicating that faster growing fish that are in better condition have lower THg concentrations. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. We used a hierarchal statistical approach to evaluate the relative importance of physiological, limnological, and catchment drivers of fish Hg concentrations. Our top statistical model explained 87% of the variability in fish THg concentrations among lakes with four key landscape and limnological variables: catchment conifer density (basal area of conifers within a lake's catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. Conifer density within a lake's catchment was the most important variable explaining fish THg concentrations across lakes, with THg concentrations differing by more than 400 percent across the forest density spectrum. These results illustrate the importance of landscape characteristics in controlling mercury bioaccumulation in fish.

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

    Science.gov (United States)

    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. © 2016 John Wiley & Sons Ltd.

  19. Remote Sensing-Derived Bathymetry of Lake Poopó

    Directory of Open Access Journals (Sweden)

    Adalbert Arsen

    2013-12-01

    Full Text Available Located within the Altiplano at 3,686 m above sea level, Lake Poopó is remarkably shallow and very sensitive to hydrologic recharge. Progressive drying has been observed in the entire Titicaca-Poopó-Desaguadero-Salar de Coipasa (TPDS system during the last decade, causing dramatic changes to Lake Poopó’s surface and its regional water supplies. Our research aims to improve understanding of Lake Poopó water storage capacity. Thus, we propose a new method based on freely available remote sensing data to reproduce Lake Poopó bathymetry. Laser ranging altimeter ICESat (Ice, Cloud, and land Elevation Satellite is used during the lake’s lowest stages to measure vertical heights with high precision over dry land. These heights are used to estimate elevations of water contours obtained with Landsat imagery. Contour points with assigned elevation are filtered and grouped in a points cloud. Mesh gridding and interpolation function are then applied to construct 3D bathymetry. Complementary analysis of Moderate Resolution Imaging Spectroradiometer (MODIS surfaces from 2000 to 2012 combined with bathymetry gives water levels and storage evolution every 8 days.

  20. Remote sensing for environmental site screening and watershed evaluation in Utah Mine lands - East Tintic mountains, Oquirrh mountains, and Tushar mountains

    Science.gov (United States)

    Rockwell, Barnaby W.; McDougal, Robert R.; Gent, Carol A.

    2005-01-01

    Imaging spectroscopy-a powerful remote-sensing tool for mapping subtle variations in the composition of minerals, vegetation, and man-made materials on the Earth's surface-was applied in support of environmental assessments and watershed evaluations in several mining districts in the State of Utah. Three areas were studied through the use of Landsat 7 ETM+ and Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data: (1) the Tintic mining district in the East Tintic Mountains southwest of Provo, (2) the Camp Floyd mining district (including the Mercur mine) and the Stockton (or Rush Valley) mining district in the Oquirrh Mountains south of the Great Salt Lake, and (3) the Tushar Mountains and Antelope Range near Marysvale. The Landsat 7 ETM+ data were used for initial site screening and the planning of AVIRIS surveys. The AVIRIS data were analyzed to create spectrally defined maps of surface minerals with special emphasis on locating and characterizing rocks and soils with acid-producing potential (APP) and acid-neutralizing potential (ANP). These maps were used by the United States Environmental Protection Agency (USEPA) for three primary purposes: (1) to identify unmined and anthropogenic sources of acid generation in the form of iron sulfide and (or) ferric iron sulfate-bearing minerals such as jarosite and copiapite; (2) to seek evidence for downstream or downwind movement of minerals associated with acid generation, mine waste, and (or) tailings from mines, mill sites, and zones of unmined hydrothermally altered rocks; and (3) to identify carbonate and other acid-buffering minerals that neutralize acidic, potentially metal bearing, solutions and thus mitigate potential environmental effects of acid generation. Calibrated AVIRIS surface-reflectance data were spectrally analyzed to identify and map selected surface materials. Two maps were produced from each flightline of AVIRIS data: a map of iron-bearing minerals and water having absorption features in the

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

    Science.gov (United States)

    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

  2. Mountain Search and Rescue with Remotely Piloted Aircraft Systems

    Science.gov (United States)

    Silvagni, Mario; Tonoli, Andrea; Zenerino, Enrico; Chiaberge, Marcello

    2016-04-01

    Remotely Piloted Aircraft Systems (RPAS) also known as Unmanned Aerial Systems (UAS) are nowadays becoming more and more popular in several applications. Even though a complete regulation is not yet available all over the world, researches, tests and some real case applications are wide spreading. These technologies can bring many benefits also to the mountain operations especially in emergencies and harsh environmental conditions, such as Search and Rescue (SAR) and avalanche rescue missions. In fact, during last decade, the number of people practicing winter sports in backcountry environment is increased and one of the greatest hazards for recreationists and professionals are avalanches. Often these accidents have severe consequences leading, mostly, to asphyxia-related death, which is confirmed by the hard drop of survival probability after ten minutes from the burying. Therefore, it is essential to minimize the time of burial. Modern avalanche beacon (ARTVA) interface guides the rescuer during the search phase reducing its time. Even if modern avalanche beacons are valid and reliable, the seeking range influences the rescue time. Furthermore, the environment and morphologic conditions of avalanches usually complicates the rescues. The recursive methodology of this kind of searching offers the opportunity to use automatic device like drones (RPAS). These systems allow performing all the required tasks autonomously, with high accuracy and without exposing the rescuers to additional risks due to secondary avalanches. The availability of highly integrated electronics and subsystems specifically meant for the applications, better batteries, miniaturized payload and, in general, affordable prices, has led to the availability of small RPAS with very good performances that can give interesting application opportunities in unconventional environments. The present work is one of the outcome from the experience made by the authors in RPAS fields and in Mechatronics

  3. POPs and other persistent organic compounds in fish from remote alpine lakes in the Grisons, Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, P.; Gujer, E.; Zennegg, M. [Swiss Federal Laboratories for Materials Testing and Research (EMPA), Duebendorf (Switzerland); Lanfranchi, M. [Agency for Nature and Environment of the Canton Grisons, Chur (Switzerland)

    2004-09-15

    Global transfer of persistent semivolatile organic compounds, such as persistent organic pollutants (POPs), is effected by long-range atmospheric transport in combination with condensation and volatilization processes. Within the global atmosphere, evaporation in warm latitudes and deposition in cold latitudes leads to a transfer of contaminants towards the poles. The phenomenon of atmospheric migration of semivolatile chemicals, such as PCB and DDT, has been predicted and associated with the term ''global distillation'' by Goldberg, and the model has been extensively reviewed by Mackay and Wania. For comparatively less volatile components such as PCDD/F and PBDE, particle-bound deposition is the dominating transfer mechanism. Therefore, the input of these compounds in remote alpine regions without point sources is controlled by atmospheric deposition (dry and wet) and condensation. For organochlorine compounds, such as pesticides and polychlorinated biphenyls (PCB), it has been shown that accumulation is enhanced by temperaturecontrolled condensation also in alpine regions with low average temperatures. The hydrology of remote alpine lakes is determined by direct atmospheric deposition feeding and feeding with water from the surrounding catchment area, without significant inputs from tributaries or from nearby anthropogenic activities. Fish dwelling in these ecosystems represents an excellent indicator for the long-term input of bioaccumulating contaminants, such as POPs and other persistent organic compounds. In the present study, fish from 7 alpine lakes from the Grisons (Switzerland) situated between 2062 and 2637 m above sea level were investigated. With the exception of Laghetto Moesola which is situated adjacent to a mountain pass road, input from local anthropogenic emissions can be excluded for these lakes.

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

    Science.gov (United States)

    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.

  5. Sedimentary records of polycyclic aromatic hydrocarbons (PAHs) in remote lakes across the Tibetan Plateau.

    Science.gov (United States)

    Yang, Ruiqiang; Xie, Ting; Li, An; Yang, Handong; Turner, Simon; Wu, Guangjian; Jing, Chuanyong

    2016-07-01

    Sediment cores from five lakes across the Tibetan Plateau were used as natural archives to study the time trends of polycyclic aromatic hydrocarbons (PAHs). The depositional flux of PAHs generally showed an increasing trend from the deeper layers towards the upper layer sediments. The fluxes of PAHs were low with little variability before the 1950s, and then gradually increased to the late 1980s, with a faster increasing rate after the 1990s. This temporal pattern is clearly different compared with those remote lakes across the European mountains when PAHs started to decrease during the period 1960s-1980s. The difference of the temporal trend was attributed to differences in the economic development stages and energy structure between these regions. PAHs are dominated by the lighter 2&3-ring homologues with the averaged percentage over 87%, while it is notable that the percentage of heavier 4-6 ring PAHs generally increased in recent years, which suggests the contribution of local high-temperature combustion sources becoming more predominant. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Recovery of acidified mountain lakes in Norway as predicted by the MAGIC model

    Directory of Open Access Journals (Sweden)

    Bernard J. COSBY

    2004-02-01

    Full Text Available As part of the EU project EMERGE the biogeochemical model MAGIC was used to reconstruct acidification history and predict future recovery for mountain lakes in two regions of Norway. Central Norway (19 lakes receives low levels of acid deposition, most of the lakes have undergone only minor amounts of acidification, and all are predicted to recover in the future. Central Norway thus represents a reference area for more polluted regions in southern Norway and elsewhere in Europe. Southern Norway (23 lakes, on the other hand, receives higher levels of acid deposition, nearly all the studied lakes were acidified and had lost fish populations, and although some recovery has occurred during the period 1980-2000 and additional recovery is predicted for the next decades, the model simulations indicated that the majority of the lakes will not achieve water quality sufficient to support trout populations. Uncertainties in these predictions include possible future N saturation and the exacerbating effects of climate change. The mountain lakes of southern Norway are among the most sensitive in Europe. For southern Norway additional measures such as stricter controls of emissions of air pollutants will be required to obtain satisfactory water quality in the future.

  7. Structure of pelagic microbial assemblages in European mountain lakes during ice-free season

    Czech Academy of Sciences Publication Activity Database

    Straškrábová, Viera; Bertoni, R.; Blažo, M.; Callieri, C.; Forsström, L.; Fott, J.; Kernan, M.; Macek, Miroslav; Stuchlík, E.; Tolotti, M.

    2009-01-01

    Roč. 62, - (2009), s. 19-53 ISSN 1612-166X Grant - others:EU MOLAR(CZ) ENV4-CT95-0007; EU EMERGE(CZ) EVK1-CT-1999-00032 Institutional research plan: CEZ:AV0Z60170517; CEZ:AV0Z6017912 Keywords : plankton * mountain lakes * microbial loop Subject RIV: EH - Ecology, Behaviour

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

    Science.gov (United States)

    Gunkel, Günter

    2003-06-01

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

  9. Remote sensing of glacier- and permafrost-related hazards in high mountains: an overview

    Directory of Open Access Journals (Sweden)

    A. Kääb

    2005-01-01

    Full Text Available Process interactions and chain reactions, the present shift of cryospheric hazard zones due to atmospheric warming, and the potential far reach of glacier disasters make it necessary to apply modern remote sensing techniques for the assessment of glacier and permafrost hazards in high-mountains. Typically, related hazard source areas are situated in remote regions, often difficult to access for physical and/or political reasons. In this contribution we provide an overview of air- and spaceborne remote sensing methods suitable for glacier and permafrost hazard assessment and disaster management. A number of image classification and change detection techniques support high-mountain hazard studies. Digital terrain models (DTMs, derived from optical stereo data, synthetic aperture radar or laserscanning, represent one of the most important data sets for investigating high-mountain processes. Fusion of satellite stereo-derived DTMs with the DTM from the Shuttle Radar Topography Mission (SRTM is a promising way to combine the advantages of both technologies. Large changes in terrain volume such as from avalanche deposits can indeed be measured even by repeat satellite DTMs. Multitemporal data can be used to derive surface displacements on glaciers, permafrost and landslides. Combining DTMs, results from spectral image classification, and multitemporal data from change detection and displacement measurements significantly improves the detection of hazard potentials. Modelling of hazardous processes based on geographic information systems (GIS complements the remote sensing analyses towards an integrated assessment of glacier and permafrost hazards in mountains. Major present limitations in the application of remote sensing to glacier and permafrost hazards in mountains are, on the one hand, of technical nature (e.g. combination and fusion of different methods and data; improved understanding of microwave backscatter. On the other hand, better

  10. Methodological issues in implementing a sustainable forest management plan in remote mountain areas - The Karakorum (Pakistan)

    OpenAIRE

    Ferrari, Efrem

    2014-01-01

    Based on a practical case-study, the Central Karakorum National Park - Gilgit-Baltistan - Pakistan, the aim of the thesis is to present a methodological framework for promoting the sustainable forest management in mountain areas characterized by remoteness, difficulties of access and where few data are available. Forest resources of Karakorum Mountains assume an essential role for the livelihoods of local communities, heavily dependent on wood for heating, cooking and construction purposes...

  11. An historical and geographic data set on the distribution of macroinvertebrates in Italian mountain lakes

    Directory of Open Access Journals (Sweden)

    Angela Boggero

    2017-11-01

    Full Text Available Macroinvertebrates play a key role in freshwater food webs, acting as major links between organic matter resources, primary consumers (such as bacteria, and secondary consumers (e.g.fish, amphibians, birds, and reptiles. In this paper we present a data set encompassing all geographic and historical data available on macroinvertebrates of the Italian mountain lakes from 1902 to 2016. The data set, divided per Italian mountain range (Alps and Apennines and administrative region, covers more than a century of studies of many foreign and Italian scientists. The data set includes 2372 records and shows macroinvertebrate occurrence data in 176 Alpine and in 13 Apennine lakes, of which 178 of natural origin, 5 reservoirs, and 6 artificially extended. The data set lists 605 taxa, updated on the basis of their current taxonomic position. Only 353 taxa are identified at species level, highlighting the still poorly investigated biodiversity of Italian mountain lake macroinvertebrates. Since they function as key elements to characterize lake ecological status, our data set emphasizes the huge taxonomic effort that still has to be undertaken to fully characterize these ecosystems. The data set is available in csv (comma-separated values format.

  12. Measured and modelled local wind field over a frozen lake in a mountainous area

    Energy Technology Data Exchange (ETDEWEB)

    Smedman, A.S.; Bergstroem, H.; Hoegstroem, U. [Uppsala Univ. (Sweden). Dept. of Meteorology

    1996-03-01

    The study is a follow-up of a previous paper and concentrates on two very characteristic flow regimes: forced channeling, where the driving geostrophic wind and the lake axis are roughly aligned, and pressure-driven channeling or gap winds, which are characterized by a geostrophic wind direction more or less perpendicular to the lake axis. Both situations produce winds along the main axis of the lake. In the forced channeling case the wind direction varies insignificantly with height and the wind speed increases monotonically with height. The gap wind flow, which can give supergeostrophic speed, is restricted to the lowest 500 m above the lake surface, drops in speed to near zero just above that layer, changing to an across-wind direction higher up. Gap winds are found to require slightly stable stratification for their existence; strong stability forces the flow to go round the mountains rather than over, and neutral conditions give a turbulent wake in the lee of the mountains. The gap wind starts at any occasion as a sudden warm front approaching from either of the two along-lake directions (115 or 295 degrees). It is argued that the relative warmth of the `gap wind air` is due to air originally flowing at mountain top height across the lake axis being gradually turned and accelerated along the synoptic pressure gradient while descending. The strongly sheared layer at the top of the gap wind region is dynamically highly unstable, giving rise to vertically coherent variations in wind speed and direction which appear to be triggered by gravity waves. When the driving geostrophic wind is high enough, the disturbed region reaches all the way down to the ground surface. Then periods with strong turbulence and low mean wind alternate with pronounced gap winds on typically a 10 minute scale. 11 refs, 18 figs

  13. New and poorly known coccoid species (Cyanoprokaryota) from the mid-depth and deep epilithon of a carbonate mountain lake

    Czech Academy of Sciences Publication Activity Database

    Cantonati, M.; Komárek, Jiří; Hernández-Mariné, M.; Angeli, N.

    2014-01-01

    Roč. 33, č. 2 (2014), s. 548-556 ISSN 2161-9549 Institutional support: RVO:67985939 Keywords : coccoid cyanobacteria * benthic epilithin * mountain lakes Subject RIV: EF - Botanics Impact factor: 1.941, year: 2014

  14. Phosphorus loading of mountain lakes: Terrestrial export and atmospheric deposition

    Czech Academy of Sciences Publication Activity Database

    Kopáček, Jiří; Hejzlar, Josef; Vrba, Jaroslav; Stuchlík, E.

    2011-01-01

    Roč. 56, č. 4 (2011), s. 1343-1354 ISSN 0024-3590 R&D Projects: GA ČR(CZ) GA206/09/1764; GA ČR(CZ) GA206/07/1200; GA ČR(CZ) GA526/09/0567 Institutional research plan: CEZ:AV0Z60170517 Keywords : oligotrophic lakes * stoichiometry * dissolved organic carbon * C:P ratio Subject RIV: DA - Hydrology ; Limnology Impact factor: 3.416, year: 2011

  15. Anthropogenic and climatic factors enhancing hypolimnetic anoxia in a temperate mountain lake

    Science.gov (United States)

    Sánchez-España, Javier; Mata, M. Pilar; Vegas, Juana; Morellón, Mario; Rodríguez, Juan Antonio; Salazar, Ángel; Yusta, Iñaki; Chaos, Aida; Pérez-Martínez, Carmen; Navas, Ana

    2017-12-01

    Oxygen depletion (temporal or permanent) in freshwater ecosystems is a widespread and globally important environmental problem. However, the factors behind increased hypolimnetic anoxia in lakes and reservoirs are often diverse and may involve processes at different spatial and temporal scales. Here, we evaluate the combined effects of different anthropogenic pressures on the oxygen dynamics and water chemistry of Lake Enol, an emblematic mountain lake in Picos de Europa National Park (NW Spain). A multidisciplinary study conducted over a period of four years (2013-2016) indicates that the extent and duration of hypolimnetic anoxia has increased dramatically in recent years. The extent and duration of hypolimnetic anoxia is typical of meso-eutrophic systems, in contrast with the internal productivity of the lake, which remains oligo-mesotrophic and phosphorus-limited. This apparent contradiction is ascribed to the combination of different external pressures in the catchment, which have increased the input of allochthonous organic matter in recent times through enhanced erosion and sediment transport. The most important among these pressures appears to be cattle grazing, which affects not only the import of carbon and nutrients, but also the lake microbiology. The contribution of clear-cutting, runoff channelling, and tourism is comparatively less significant. The cumulative effects of these local human impacts are not only affecting the lake metabolism, but also the import of sulfate, nitrate- and ammonium-nitrogen, and metals (Zn). However, these local factors alone cannot explain entirely the observed oxygen deficit. Climatic factors (e.g., warmer and drier spring and autumn seasons) are also reducing oxygen levels in deep waters through a longer and increasingly steep thermal stratification. Global warming may indirectly increase anoxia in many other mountain lakes in the near future.

  16. Hydrologic and Isotopic Sensitivity of Alpine Lakes to Climate Change in the Medicine Bow Mountains, Wyoming

    Science.gov (United States)

    Liefert, D. T.; Shuman, B. N.; Mercer, J.; Parsekian, A.; Williams, D. G.

    2017-12-01

    Climate reconstructions show that global average temperatures were 0.5°C higher than today during the mid-Holocene, falling well within projections for increases in global average temperature presented in the latest Intergovernmental Panel on Climate Change report. Despite the consensus for the prediction of a warmer climate, however, it is unclear how snowmelt from high-elevation watersheds will be affected by such a change. Snowmelt contributes substantially to major rivers in the western United States, and much of the water flows through lakes in the highest-elevation watersheds. Our water balance models show that modern alpine lakes with seasonably unstable water levels can desiccate primarily through groundwater outflow, resulting in increased groundwater storage that likely sustains baseflow in mountain streams once snowmelt has subsided in late summer. However, contribution of freshwater from alpine lakes to streams may vary over time as changes in climate alters snowpack, rates of evaporation, and the abundance of snowmelt-fed lakes. As such, alpine lakes with seasonally unstable water levels today may have dried out entirely during the mid-Holocene warm period and may dry out in the future as temperatures increase. To investigate the response of alpine lakes to temperatures of the mid-Holocene, we collected 9 sediment cores from closed-basin alpine lakes in the Medicine Bow Mountains of southern Wyoming that lose most their volumes each summer. We use radiocarbon-dating of charcoal in basal sediments to determine lake formation age, abundance of conifer needles to infer relative forest cover, and a δ18O carbonate record to determine changes in the ratio of evaporation to precipitation in an alpine lake that existed throughout the Holocene. Warming likely changed watershed hydrology through a) decreased snowpack and earlier snowmelt, b) increased evaporation, and c) increased transpiration associated with expanded forest cover and longer growing seasons

  17. Studies on algea of Da′erbin lake and its surrounding swamps in daxing anling mountain

    Directory of Open Access Journals (Sweden)

    LI Xiaofei

    2012-08-01

    Full Text Available The paper reports 234 taxa of algae (excluding diatomas and desmids in Da′erbin Lake and its surrounding swamps in the Great Xing′an Mountains.They were identified belong to 6 phylums 79 generas 197 species 31 varieties and 6 forms.Among them Characium ornithocephalum var.pringsheimii (A.Br. Kom.,Characium pluricoccum Kor.,Quadrigula korsikovii Kom.,Crucigeniella rectangularis (Ng. Kom.are newly reported in China.

  18. Distribution and interannual variability of supraglacial lakes on debris-covered glaciers in the Khan Tengri-Tumor Mountains, Central Asia

    International Nuclear Information System (INIS)

    Qiao, Liu; Mayer, Christoph; Liu, Shiyin

    2015-01-01

    Supraglacial lakes are widely formed on debris-covered glaciers in the Khan Tengri-Tumor Mountains (KTTM), Tianshan, Central Asia. Study of their distribution characters based on regional-wide remote sensing investigations is still lacking, but it can promote our understanding about the influence of supraglacial lakes on the surface melting, hydrology and dynamics of debris-covered glaciers in this region. This study presents results of the supraglacial lake inventory in the KTTM region, based on multi-year Landsat images. We focus on the glacio-geomorphological characters of the supraglacial lakes and their late summer conditions, since all suitable Landsat images were acquired between August and September during 1990–2011. With a minimum threshold extent of 3600 m 2 for conservative mapping results, we totally mapped 775 supraglacial lakes and 38 marginal glacial lakes on eight huge debris-covered glaciers. Supraglacial lakes are concentrated on the Tumor Glacier and the South Inylchek Glacier, two biggest glaciers in this region. Although most supraglacial lakes are short-lived, a number of lakes can be repeatedly identified between different Landsat images. Detailed investigation of these ‘perennial’ lakes on the Tumor Glacier indicates that their filling frequency and area contributions have increased since 2005. Analysis of the area-elevation distributions for all mapped supraglacial lakes shows that they predominantly occur close to the altitude of 3250 m a.s.l., as high as the lowest reach of clean ice where surface debris begins to appear, and can further develop upglacier to a limit of about 3950 m a.s.l.. Total and mean area of supraglacial lakes in the KTTM region during the late summer seasons show great variability between years. Correlation analysis between the annual lake area and the observed nearby meteorological conditions suggests that warmer springs seem related to the draining of some supraglacial lakes during the following seasons, due

  19. REMOTE MATERIAL HANDLING IN THE YUCCA MOUNTAIN WASTE PACKAGE CLOSURE CELL AND SUPPORT AREA GLOVEBOX

    International Nuclear Information System (INIS)

    K.M. Croft; S.M. Allen; M.W. Borland

    2005-01-01

    The Yucca Mountain Waste Package Closure System (WPCS) cells provide for shielding of highly radioactive materials contained in unsealed waste packages. The purpose of the cells is to provide safe environments for package handling and sealing operations. Once sealed, the packages are placed in the Yucca Mountain Repository. Closure of a typical waste package involves a number of remote operations. Those involved typically include the placement of matched lids onto the waste package. The lids are then individually sealed to the waste package by welding. Currently, the waste package includes three lids. One lid is placed before movement of the waste package to the closure cell; the final two are placed inside the closure cell, where they are welded to the waste package. These and other important operations require considerable remote material handling within the cell environment. This paper discusses the remote material handling equipment, designs, functions, operations, and maintenance, relative to waste package closure

  20. Remote Sensing of Lake Ice Phenology in Alaska

    Science.gov (United States)

    Zhang, S.; Pavelsky, T.

    2017-12-01

    Lake ice phenology (e.g. ice break-up and freeze-up timing) in Alaska is potentially sensitive to climate change. However, there are few current lake ice records in this region, which hinders the comprehensive understanding of interactions between climate change and lake processes. To provide a lake ice database with over a comparatively long time period (2000 - 2017) and large spatial coverage (4000+ lakes) in Alaska, we have developed an algorithm to detect the timing of lake ice using Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data. This approach generally consists of three major steps. First, we use a cloud mask (MOD09GA) to filter out satellite images with heavy cloud contamination. Second, daily MODIS reflectance values (MOD09GQ) of lake surface are used to extract ice pixels from water pixels. The ice status of lakes can be further identified based on the fraction of ice pixels. Third, to improve the accuracy of ice phenology detection, we execute post-processing quality control to reduce false ice events caused by outliers. We validate the proposed algorithm over six lakes by comparing with Landsat-based reference data. Validation results indicate a high correlation between the MODIS results and reference data, with normalized root mean square error (NRMSE) ranging from 1.7% to 4.6%. The time series of this lake ice product is then examined to analyze the spatial and temporal patterns of lake ice phenology.

  1. NO3 uptake in shallow, oligotrophic, mountain lakes: The influence of elevated NO3 concentrations

    Science.gov (United States)

    Nydick, K.R.; LaFrancois, B.M.; Baron, Jill S.

    2004-01-01

    Nutrient enrichment experiments were conducted in 1.2-m deep enclosures in 2 shallow, oligotrophic, mountain lakes. 15N-NO3 isotope tracer was used to compare the importance of phytoplankton and benthic compartments (epilithon, surface sediment [epipelon], and subsurface sediment) for NO3 uptake under high and low NO3 conditions. NO3 uptake approached saturation in the high-N lake, but not in the low-N lake. The capacity of phytoplankton and benthic compartments to take up NO3 differed among treatments and between lakes, and depended on water-column nutrient conditions and the history of NO3 availability. Phytoplankton productivity responded strongly to addition of limiting nutrients, and NO3 uptake was related to phytoplankton biomass and photosynthesis. However, more NO3 usually was taken up by benthic compartments (57–92% combined) than by phytoplankton, even though the response of benthic algal biomass to nutrient additions was less pronounced than that of phytoplankton and benthic NO3 uptake was unrelated to benthic algal biomass. In the low-N lake where NO3 uptake was unsaturated, C content or % was related to NO3 uptake in benthic substrates, suggesting that heterotrophic bacterial processes could be important in benthic NO3 uptake. These results suggest that phytoplankton are most sensitive to nutrient additions, but benthic processes are important for NO3 uptake in shallow, oligotrophic lakes.

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

    Science.gov (United States)

    Laney, R.L.

    1981-01-01

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

  3. High-frequency remote monitoring of large lakes with MODIS 500 m imagery

    Science.gov (United States)

    McCullough, Ian M.; Loftin, Cynthia S.; Sader, Steven A.

    2012-01-01

    Satellite-based remote monitoring programs of regional lake water quality largely have relied on Landsat Thematic Mapper (TM) owing to its long image archive, moderate spatial resolution (30 m), and wide sensitivity in the visible portion of the electromagnetic spectrum, despite some notable limitations such as temporal resolution (i.e., 16 days), data pre-processing requirements to improve data quality, and aging satellites. Moderate-Resolution Imaging Spectroradiometer (MODIS) sensors on Aqua/Terra platforms compensate for these shortcomings, although at the expense of spatial resolution. We developed and evaluated a remote monitoring protocol for water clarity of large lakes using MODIS 500 m data and compared MODIS utility to Landsat-based methods. MODIS images captured during May–September 2001, 2004 and 2010 were analyzed with linear regression to identify the relationship between lake water clarity and satellite-measured surface reflectance. Correlations were strong (R² = 0.72–0.94) throughout the study period; however, they were the most consistent in August, reflecting seasonally unstable lake conditions and inter-annual differences in algal productivity during the other months. The utility of MODIS data in remote water quality estimation lies in intra-annual monitoring of lake water clarity in inaccessible, large lakes, whereas Landsat is more appropriate for inter-annual, regional trend analyses of lakes ≥ 8 ha. Model accuracy is improved when ancillary variables are included to reflect seasonal lake dynamics and weather patterns that influence lake clarity. The identification of landscape-scale drivers of regional water quality is a useful way to supplement satellite-based remote monitoring programs relying on spectral data alone.

  4. Remotely Sensing Lake Water Volumes on the Inner Arctic Coastal Plain of Northern Alaska

    Science.gov (United States)

    Simpson, C. E.; Arp, C. D.; Jones, B. M.; Hinkel, K. M.; Carroll, M.; Smith, L. C.

    2017-12-01

    Thermokarst lake depth is controlled by the amount of excess ice in near-surface permafrost, with lake depths of about 1 - 3 m in areas of epigenetic permafrost and over 10 m in areas of syngenetic permafrost. An important exception to these general patterns is found on the inner Arctic Coastal Plain (ACP) of northern Alaska, where deep lakes occur in Pleistocene-aged, ground-ice poor sandy terrain. These lakes cover 20% of the currently inactive sand sheet and dune deposit (referred to as the Pleistocene Sand Sea) that comprises approximately 7000 km2 of the ACP. Surrounded by high and eroding bluffs, sand sea lakes lie in natural depressions and are characterized by wide, shallow littoral shelves and central troughs that are typically oriented NNW to SSE and can reach depths greater than 20 m. Despite their unique form and extensive coverage, these lakes have received little prior study and a literature gap remains regarding regional water storage. This research classifies sand sea lakes, estimates individual lake volume, and provides a first quantification of water storage in a region of the lake-dominated ACP. We measured bathymetric profiles in 19 sand sea lakes using a sonar recorder to capture various lake depth gradients. Bathymetric surveys collected by oil industry consultants, lake monitoring programs, and habitat studies serve as additional datasets. These field measured lake depth data points were used to classify Color Infrared Photography, WorldView-2 satellite imagery, and Landsat-OLI satellite imagery to develop a spectral depth-classification algorithm and facilitate the interpolation of the bathymetry for study lakes in the inner ACP. Finally, we integrate the remotely sensed bathymetry and imagery-derived lake surface area to estimate individual and regional-scale lake volume. In addition to the natural function of these lakes in water storage, energy balance, and habitat provision, the need for winter water supply to build ice roads for oil

  5. Assessing climate change impacts on water resources in remote mountain regions

    Science.gov (United States)

    Buytaert, Wouter; De Bièvre, Bert

    2013-04-01

    From a water resources perspective, remote mountain regions are often considered as a basket case. They are often regions where poverty is often interlocked with multiple threats to water supply, data scarcity, and high uncertainties. In these environments, it is paramount to generate locally relevant knowledge about water resources and how they impact local livelihoods. This is often problematic. Existing environmental data collection tends to be geographically biased towards more densely populated regions, and prioritized towards strategic economic activities. Data may also be locked behind institutional and technological barriers. These issues create a "knowledge trap" for data-poor regions, which is especially acute in remote and hard-to-reach mountain regions. We present lessons learned from a decade of water resources research in remote mountain regions of the Andes, Africa and South Asia. We review the entire tool chain of assessing climate change impacts on water resources, including the interrogation and downscaling of global circulation models, translating climate variables in water availability and access, and assessing local vulnerability. In global circulation models, mountain regions often stand out as regions of high uncertainties and lack of agreement of future trends. This is partly a technical artifact because of the different resolution and representation of mountain topography, but it also highlights fundamental uncertainties in climate impacts on mountain climate. This problem also affects downscaling efforts, because regional climate models should be run in very high spatial resolution to resolve local gradients, which is computationally very expensive. At the same time statistical downscaling methods may fail to find significant relations between local climate properties and synoptic processes. Further uncertainties are introduced when downscaled climate variables such as precipitation and temperature are to be translated in hydrologically

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

    Science.gov (United States)

    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.

  7. MORPHO-BATHYMETRIC PARAMETERS OF RECESS CRUCII LAKE (STÂNIŞOAREI MOUNTAINS

    Directory of Open Access Journals (Sweden)

    ALIN MIHU-PINTILIE

    2012-03-01

    Full Text Available Morpho-bathymetric parameters of recess Crucii Lake (Stânişoarei Mountains. Crucii Lake from Stânişoarei Mountains was formed in 1978 as a result of riverbed dam Cuejdel after a landslide triggered on the western slope of Muncelul Peak. The event led initially to a small accumulation of 250-300 acvatoriu m, 25-30 m wide and 4-5 m maximum depth. In the summer of 1991 following the construction of a forest road in the flysch, and amid a high humid conditions, the slide was reactivated, leading to the formation of the largest natural dam lake in Romania. It has a length of 1 km, area of 12.2 ha, maximum depth of 16 m and a water volume of ca. 907.000 m3. Morphometric and morpho-bathymetric measurements performed in the summer of 2011, with the help of the integrated 1.200 GPS of Station Leica System 1.200 surveying measurements and bathymetric measurements Valeyport Ecosounder Midas showed new values for the morpho-bathymetric parameters. Among them stands out: 13,95 ha area, perimeter 2801,1 m, maximum length of 1004,82 m, 282,6 m maximum width, maximum depth 16,45 m. To achieve the numerical model of the lake basin were more than 45.000 points bali reading, with equidistance of 0,25 m. The scale of detail work aimed to draw up a proper database to eliminate suspicions about the old analytical methods inaccuracies. At the same time was studied the evolution of the lake’s basin in the context of relatively recent geomorphological changes.

  8. CURRENT MICROBIOLOGICAL ASPECTS IN HIGH MOUNTAIN

    OpenAIRE

    KURT HANSELMANN; MUNTI YUHANA

    2006-01-01

    Remote and normally unpolluted high mountain lakes provide habitats with no or very limited anthropogenic influences and, therefore, their hydrodynamics are mostly regulated by the natural c onditions. Researches in high mountain lakes deal with measuring and modeling the response of the habitats to environmental changes especially correlated to acid deposition, pollutants influx and climatic variability. The microbial world has also become a focus in many studies of these extreme ecosystem...

  9. Mountainous Ecosystem Sensor Array (MESA): a mesh sensor network for climate change research in remote mountainous environments

    Science.gov (United States)

    Robinson, P. W.; Neal, D.; Frome, D.; Kavanagh, K.; Davis, A.; Gessler, P. E.; Hess, H.; Holden, Z. A.; Link, T. E.; Newingham, B. A.; Smith, A. M.

    2013-12-01

    Developing sensor networks robust enough to perform unattended in the world's remote regions is critical since these regions serve as important benchmarks that lack anthropogenic influence. Paradoxically, the factors that make these remote, natural sites challenging for sensor networking are often what make them indispensable for climate change research. The MESA (Mountainous Ecosystem Sensor Array) project has faced these challenges and developed a wireless mesh sensor network across a 660 m topoclimatic gradient in a wilderness area in central Idaho. This sensor array uses advances in sensing, networking, and power supply technologies to provide near real-time synchronized data covering a suite of biophysical parameters used in ecosystem process models. The 76 sensors in the network monitor atmospheric carbon dioxide concentration, humidity, air and soil temperature, soil water content, precipitation, incoming and outgoing shortwave and longwave radiation, snow depth, wind speed and direction, and leaf wetness at synchronized time intervals ranging from two minutes to two hours and spatial scales from a few meters to two kilometers. We present our novel methods of placing sensors and network nodes above, below, and throughout the forest canopy without using meteorological towers. In addition, we explain our decision to use different forms of power (wind and solar) and the equipment we use to control and integrate power harvesting. Further, we describe our use of the network to sense and quantify its own power use. Using examples of environmental data from the project, we discuss how these data may be used to increase our understanding of the effects of climate change on ecosystem processes in mountainous environments. MESA sensor locations across a 700 m topoclimatic gradient at the University of Idaho Taylor Wilderness Research Station.

  10. Denitrification and Biodiversity of Denitrifiers in a High-Mountain Mediterranean Lake

    Directory of Open Access Journals (Sweden)

    Antonio Castellano-Hinojosa

    2017-10-01

    Full Text Available Wet deposition of reactive nitrogen (Nr species is considered a main factor contributing to N inputs, of which nitrate (NO3− is usually the major component in high-mountain lakes. The microbial group of denitrifiers are largely responsible for reduction of nitrate to molecular dinitrogen (N2 in terrestrial and aquatic ecosystems, but the role of denitrification in removal of contaminant nitrates in high-mountain lakes is not well understood. We have used the oligotrophic, high-altitude La Caldera lake in the Sierra Nevada range (Spain as a model to study the role of denitrification in nitrate removal. Dissolved inorganic Nr concentration in the water column of la Caldera, mainly nitrate, decreased over the ice-free season which was not associated with growth of microbial plankton or variations in the ultraviolet radiation. Denitrification activity, estimated as nitrous oxide (N2O production, was measured in the water column and in sediments of the lake, and had maximal values in the month of August. Relative abundance of denitrifying bacteria in sediments was studied by quantitative polymerase chain reaction of the 16S rRNA and the two phylogenetically distinct clades nosZI and nosZII genes encoding nitrous oxide reductases. Diversity of denitrifiers in sediments was assessed using a culture-dependent approach and after the construction of clone libraries employing the nosZI gene as a molecular marker. In addition to genera Polymorphum, Paracoccus, Azospirillum, Pseudomonas, Hyphomicrobium, Thauera, and Methylophaga, which were present in the clone libraries, Arthrobacter, Burkholderia, and Rhizobium were also detected in culture media that were not found in the clone libraries. Analysis of biological activities involved in the C, N, P, and S cycles from sediments revealed that nitrate was not a limiting nutrient in the lake, allowed N2O production and determined denitrifiers’ community structure. All these results indicate that

  11. Denitrification and Biodiversity of Denitrifiers in a High-Mountain Mediterranean Lake

    Science.gov (United States)

    Castellano-Hinojosa, Antonio; Correa-Galeote, David; Carrillo, Presentación; Bedmar, Eulogio J.; Medina-Sánchez, Juan M.

    2017-01-01

    Wet deposition of reactive nitrogen (Nr) species is considered a main factor contributing to N inputs, of which nitrate (NO3−) is usually the major component in high-mountain lakes. The microbial group of denitrifiers are largely responsible for reduction of nitrate to molecular dinitrogen (N2) in terrestrial and aquatic ecosystems, but the role of denitrification in removal of contaminant nitrates in high-mountain lakes is not well understood. We have used the oligotrophic, high-altitude La Caldera lake in the Sierra Nevada range (Spain) as a model to study the role of denitrification in nitrate removal. Dissolved inorganic Nr concentration in the water column of la Caldera, mainly nitrate, decreased over the ice-free season which was not associated with growth of microbial plankton or variations in the ultraviolet radiation. Denitrification activity, estimated as nitrous oxide (N2O) production, was measured in the water column and in sediments of the lake, and had maximal values in the month of August. Relative abundance of denitrifying bacteria in sediments was studied by quantitative polymerase chain reaction of the 16S rRNA and the two phylogenetically distinct clades nosZI and nosZII genes encoding nitrous oxide reductases. Diversity of denitrifiers in sediments was assessed using a culture-dependent approach and after the construction of clone libraries employing the nosZI gene as a molecular marker. In addition to genera Polymorphum, Paracoccus, Azospirillum, Pseudomonas, Hyphomicrobium, Thauera, and Methylophaga, which were present in the clone libraries, Arthrobacter, Burkholderia, and Rhizobium were also detected in culture media that were not found in the clone libraries. Analysis of biological activities involved in the C, N, P, and S cycles from sediments revealed that nitrate was not a limiting nutrient in the lake, allowed N2O production and determined denitrifiers’ community structure. All these results indicate that denitrification could be a

  12. Solar power and the possibility of socio-economic development in the remote and mountainous areas of Uzbekistan

    International Nuclear Information System (INIS)

    Zainutdinova, Kh. K.; Lutpullaev, S. L.

    2011-01-01

    The possibility of socio-economic development in remote and mountainous areas of Uzbekistan in the context of using solar energy on the grounds of the past experience of different countries is discussed in this article. The obstacles to using solar energy in remote areas and the approaches to overcoming them are described. (authors)

  13. Hydrodynamic and Inundation Modeling of China’s Largest Freshwater Lake Aided by Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    2015-04-01

    Full Text Available China’s largest freshwater lake, Poyang Lake, is characterized by rapid changes in its inundation area and hydrodynamics, so in this study, a hydrodynamic model of Poyang Lake was established to simulate these long-term changes. Inundation information was extracted from Moderate Resolution Imaging Spectroradiometer (MODIS remote sensing data and used to calibrate the wetting and drying parameter by assessing the accuracy of the simulated inundation area and its boundary. The bottom friction parameter was calibrated using current velocity measurements from Acoustic Doppler Current Profilers (ADCP. The results show the model is capable of predicting the inundation area dynamic through cross-validation with remotely sensed inundation data, and can reproduce the seasonal dynamics of the water level, and water discharge through a comparison with hydrological data. Based on the model results, the characteristics of the current velocities of the lake in the wet season and the dry season of the lake were explored, and the potential effect of the current dynamic on water quality patterns was discussed. The model is a promising basic tool for prediction and management of the water resource and water quality of Poyang Lake.

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

    Science.gov (United States)

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

    2015-01-01

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

  15. Remote sensing monitoring on soil erosion based on LUCC in Beijing mountain areas

    International Nuclear Information System (INIS)

    Gaiying, Chen

    2014-01-01

    The eco-environmental problems caused by land use and land cover change have been a severe block to regional sustainable development in the Beijing mountain areas. In this study, two temporal Landsat TM images in 2002 and 2009 were used, the soil erosion factors included vegetation coverage, slope and land use were calculated. The soil erosion degree was divided into six levels, micro, mild, moderate, strong, intensive and severe. The raster data with 30 m × 30 m pixels small-class of the soil erosion map was used to extract soil erosion information. This thesis evaluated soil erosion dynamic in Beijing mountain areas based on land use and land cover change with the combination of technologies and methodologies of multi-temporal satellite remote sensing, GIS and field investigation. The soil erosion change and their driving forces were analysed. The results showed micro and mild soil erosion mainly existed in the Beijing mountain areas. The moderate erosion emerged in the areas with both slope and poor vegetation cover. The strong, intensive and severe soil erosion were rare but distributed in mountainous areas in Huairou, Miyun, and Mentougou. The soil erosion situation has improved markedly due to environment management from 2002 to 2009

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

    Science.gov (United States)

    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

  17. Vegetation Diversity Quality in Mountainous Forest of Ranu Regulo Lake Area, Bromo Tengger Semeru National Park, East Java

    Directory of Open Access Journals (Sweden)

    Jehan Ramdani Hariyati

    2012-01-01

    Full Text Available Aim of this research was to study vegetation diversity quality in mountainous forest of Ranu Regulo Lake area in Bromo Tengger Semeru National Park (TNBTS, East Java. Field observation was carried out by vegetation analysis using sampling plots of 25x25 m2 for trees, 5x5 m2 for poles, 1x1 m2 for ground surface plants. Community structure of each lake side was determined by calculating vegetation's density, basal area, frequency, important value and stratification of species. While vegetations diversity was estimated by taxa richness, Shannon-Wiener diversity index, and rate of endemism. Each lake side forests were compared by Morisita community similarity index. Data were tabulated by Microsoft Excel 2007. The result showed that based on existed vegetation, mountainous forest surrounding Ranu Regulo Lake consisted of four ecosystems, i.e. heterogenic mountainous forest, pine forest, acacia forest and bushes. Bushes Area has two types of population, edelweiss and Eupatorium odoratum invaded area. Vegetation diversity quality in heterogenic mountainous forest of Ranu Regulo TNBTS was the highest, indicated by its multi-stratification to B stratum trees of 20-30m high. Heterogenic mountainous forest’s formation was Acer laurinum and Acmena accuminatissima for trees, Chyatea for poles. Taxa richness was found 59 species and 30 families, while the others were found below 28 species and 17 families. Diversity Index of heterogenic mountainous forest is the highest among others for trees is 2.31 and 3.24 for poles and second in bushes (H=3.10 after edelweiss ecosystem (H=3.39. Highest rate of endemism reached 100% for trees in heterogenic mountainous forest, 87% for poles in edelweiss area and 89% for bushes also in heterogenic mountainous forest. Trees, poles and herbs most similarity community showed by pine and acacia forest. Based on those five characters, vegetation diversity quality in Ranu Regulo Lake area was medium for heterogenic mountainous

  18. Assessment of Lake Water Quality and Quantity Using Satellite Remote Sensing

    Science.gov (United States)

    Daniel, K. C.; Suresh, A.; Paredes Mesa, S.

    2017-12-01

    Lakes are one of the few sources of freshwater used throughout the world but due to human activities, its quality and availability has been decreasing. The drying of lakes is a concerning issue in different communities around the world. This problem can affect jobs and the lives of individuals who use lakes as a source of income, consumption and recreation. Another dilemma that has occurred in lakes is eutrophication which is the buildup of excess nutrients in the lakes caused by runoff. This natural process can lead to anoxic conditions that may have a detrimental impact on surrounding ecosystems. Therefore, causing a devastating impact to economies and human livelihood worldwide. To monitor these issues, satellite data can be used to assess the water quality of different lakes throughout the world. Landsat satellite data from the past 10 years was used to conduct this research. By using the IOP (Inherent Optical Properties) of chlorophyll and suspended solids in the visible spectrum, the presence of algal blooms and sediments was determined. ARCGIS was used to outline the areas of the lakes and obtain reflectance values for quantity and quality assessment. Because there is always a certain amount of contamination in the lake, this research is used to evaluate the condition of the lakes throughout the years. Using the data that we have collected, we are able to understand how the issues addressed can harm civilians seasonally. Key Words: Lakes, Water Quality, Algal Blooms, Eutrophication, Remote Sensing, Satellite DataData Source: Landsat 4, Landsat 5, Landsat 7, Landsat 8

  19. Bacterioplankton community composition along a salinity gradient of sixteen high-mountain lakes located on the Tibetan Plateau, China

    NARCIS (Netherlands)

    Wu, Q.L.; Zwart, G.; Schauer, M.; Kamst-van Agterveld, M.P.; Hahn, M.W.

    2006-01-01

    The influence of altitude and salinity on bacterioplankton community composition (BCC) in 16 high-mountain lakes located at altitudes of 2,817 to 5,134 m on the Eastern Qinghai-Xizang (Tibetan) Plateau, China, spanning a salinity gradient from 0.02% (freshwater) to 22.3% (hypersaline), was

  20. Special Forest Products on the Green Mountain and Finger Lakes National Forests: a research-based approach to management

    Science.gov (United States)

    Marla R. Emery; Clare. Ginger

    2014-01-01

    Special forest products (SFPs) are gathered from more than 200 vascular and fungal species on the Green Mountain National Forest (GMNF) and Finger Lakes National Forest (FLNF). This report documents those SFPs and proposes an approach to managing them in the context of legislation directing the U.S. Forest Service to institute a program of active SFP management. Based...

  1. Zooplankton abundance, species composition and ecology of tropical high-mountain crater lake Wonchi, Ethiopia

    Directory of Open Access Journals (Sweden)

    Fasil Degefu

    2014-11-01

    Full Text Available The highlands of Ethiopia represent some of the remnants of undisturbed aquatic ecosystems; they are however highly threatened by significant socio–economic developments and associated anthropogenic impacts. Lake Wonchi is one of the few remaining fairly pristine high–mountain crater lakes in the central highlands and has never been investigated in detail. We present a first study on zooplankton taxa composition, abundance and biomass conducted over more than one year including the underlying environmental drivers. The lake is basic (pH 7.9-8.9, dilute (specific conductivity 185-245 µS cm-1 and oligotrophic with mean trophic status index of 36. The zooplankton community composition showed low species richness comprising a total of fourteen taxa with six cladocerans, one copepod and seven rotifers. Simpson´s index of diversity with values between 0.6 and 0.8 pointed towards a homogenous taxa occurrence within the single sample units. The overall mean (±SD standing biomass of zooplankton was 62.02±25.76 mg dry mass m-3,which is low compared to other highland and rift valley lakes in Ethiopia. Cyclopoid copepods, in particular Thermocyclops ethiopiensis were the most abundant group and contributed 50% to the total zooplankton abundance followed by cladocerans (38% and rotifers (12%. Non-metric multi-dimensional scaling resulted in a 3-dimensional model, which revealed similar community composition on successive sampling dates except in December/January and May. Temperature, alkalinity, conductivity and nitrate-N had significant influence on this seasonal pattern. A weak, but significant positive correlation (r=0.482, N=20, P=0.037 between Chlorophyll a and zooplankton biomass mirrors a bottom-up effect of phytoplankton biomass on zooplankton dynamics. The zooplankton of Lake Wonchi displayed some degree of segregation along the epi– and metalimnion during this study, but diel vertical migration was not observed. The results show that fish

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

    Science.gov (United States)

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

    2017-07-15

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

  3. Developing A Model for Lake Ice Phenology Using Satellite Remote Sensing Observations

    Science.gov (United States)

    Skoglund, S. K.; Weathers, K. C.; Norouzi, H.; Prakash, S.; Ewing, H. A.

    2017-12-01

    Many northern temperate freshwater lakes are freezing over later and thawing earlier. This shift in timing, and the resulting shorter duration of seasonal ice cover, is expected to impact ecological processes, negatively affecting aquatic species and the quality of water we drink. Long-term, direct observations have been used to analyze changes in ice phenology, but those data are sparse relative to the number of lakes affected. Here we develop a model to utilize remote sensing data in approximating the dates of ice-on and ice-off for many years over a variety of lakes. Day and night surface temperatures from MODIS (Moderate Resolution Imaging Spectroradiometer) Aqua and Terra (MYD11A1 and MOD11A1 data products) for 2002-2017 were utilized in combination with observed ice-on and ice-off dates of Lake Auburn, Maine, to determine the ability of MODIS data to match ground-based observations. A moving average served to interpolate MODIS temperature data to fill data gaps from cloudy days. The nighttime data were used for ice-off, and the daytime measurements were used for ice-on predictions to avoid fluctuations between day and night ice/water status. The 0˚C intercepts of those data were used to mark approximate days of ice-on or ice-off. This revealed that approximations for ice-off dates were satisfactory (average ±8.2 days) for Lake Auburn as well as for Lake Sunapee, New Hampshire (average ±8.1 days), while approximations for Lake Auburn ice-on were less accurate and showed consistently earlier-than-observed ice-on dates (average -33.8 days). The comparison of observed and remotely sensed Lake Auburn ice cover duration showed relative agreement with a correlation coefficient of 0.46. Other remote sensing observations, such as the new GOES-R satellite, and further exploration of the ice formation process can improve ice-on approximation methods. The model shows promise for estimating ice-on, ice-off, and ice cover duration for northern temperate lakes.

  4. Relating Hydrogeomorphic Attributes to Nutrient Uptake in Alluvial Streams of a Mountain Lake District

    Science.gov (United States)

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

    2005-05-01

    Stream form and hydrologic processes may indirectly drive nutrient uptake, however developing predictive relationships has been elusive. Problems in establishing such relationships may lie in the sets of streams analyzed, which often span diverse channel-sizes, geology, and regions, or are too geomorphically similar. We collected field data on stream geomorphology and hydrologic and nutrient transport processes using solute injections at 22 alluvial stream reaches in the Sawtooth Mountains, Idaho, USA. Many of these streams occur near lakes, which create contrasting fluvial form and functions that we hoped would produce a broad geomorphic dataset to compare to hyporheic and dead-zone transient storage and NO3 and PO4 spiraling metrics. Preliminary results suggest that storage zone residence time (Tsto) was best predicted by sediment D50, wood abundance (CWD), and discharge (r2=0.84, pnutrient cycling processes should be further considered and investigated.

  5. Monitoring of Calcite Precipitation in Hardwater Lakes with Multi-Spectral Remote Sensing Archives

    Directory of Open Access Journals (Sweden)

    Iris Heine

    2017-01-01

    Full Text Available Calcite precipitation is a common phenomenon in calcium-rich hardwater lakes during spring and summer, but the number and spatial distribution of lakes with calcite precipitation is unknown. This paper presents a remote sensing based method to observe calcite precipitation over large areas, which are an important prerequisite for a systematic monitoring and evaluation of restoration measurements. We use globally archived satellite remote sensing data for a retrospective systematic assessment of past multi-temporal calcite precipitation events. The database of this study consists of 205 data sets that comprise freely available Landsat and Sentinel 2 data acquired between 1998 and 2015 covering the Northeast German Plain. Calcite precipitation is automatically identified using the green spectra and the metric BGR area, the triangular area between the blue, green and red reflectance value. The validation is based on field measurements of CaCO3 concentrations at three selected lakes, Feldberger Haussee, Breiter Luzin and Schmaler Luzin. The classification accuracy (0.88 is highest for calcite concentrations ≥0.7 mg/L. False negative results are caused by the choice of a conservative classification threshold. False positive results can be explained by already increased calcite concentrations. We successfully transferred the developed method to 21 other hardwater lakes in Northeast Germany. The average duration of lakes with regular calcite precipitation is 37 days. The frequency of calcite precipitation reaches from single time detections up to detections nearly every year. False negative classification results and gaps in Landsat time series reduce the accuracy of frequency and duration monitoring, but in future the image density will increase by acquisitions of Sentinel-2a (and 2b. Our study tested successfully the transfer of the classification approach to Sentinel-2 images. Our study shows that 15 of the 24 lakes have at least one phase of

  6. Remotely Sensed Based Lake/Reservoir Routing in Congo River Basin

    Science.gov (United States)

    Raoufi, R.; Beighley, E.; Lee, H.

    2017-12-01

    Lake and reservoir dynamics can influence local to regional water cycles but are often not well represented in hydrologic models. One challenge that limits their inclusion in models is the need for detailed storage-discharge behavior that can be further complicated in reservoirs where specific operation rules are employed. Here, the Hillslope River Routing (HRR) model is combined with a remotely sensed based Reservoir Routing (RR) method and applied to the Congo River Basin. Given that topographic data are often continuous over the entire terrestrial surface (i.e., does not differentiate between land and open water), the HRR-RR model integrates topographic derived river networks and catchment boundaries (e.g., HydroSHEDs) with water boundary extents (e.g., Global Lakes and Wetlands Database) to develop the computational framework. The catchments bordering lakes and reservoirs are partitioned into water and land portions, where representative flowpath characteristics are determined and vertical water balance and lateral routings is performed separately on each partition based on applicable process models (e.g., open water evaporation vs. evapotranspiration). To enable reservoir routing, remotely sensed water surface elevations and extents are combined to determine the storage change time series. Based on the available time series, representative storage change patterns are determined. Lake/reservoir routing is performed by combining inflows from the HRR-RR model and the representative storage change patterns to determine outflows. In this study, a suite of storage change patterns derived from remotely sensed measurements are determined representative patterns for wet, dry and average conditions. The HRR-RR model dynamically selects and uses the optimal storage change pattern for the routing process based on these hydrologic conditions. The HRR-RR model results are presented to highlight the importance of lake attenuation/routing in the Congo Basin.

  7. Study of the wide area of a lake with remote sensing

    Science.gov (United States)

    Lazaridou, Maria A.; Karagianni, Aikaterini C.

    2016-08-01

    Water bodies are particularly important for environment and development issues. Their study requires multiple information. Remote sensing has been proven useful in the above study. This paper concerns the wide area of Lake Orestiada in the region of Western Macedonia in Greece. The area is of particular interest because Lake Orestiada is included in the Natura 2000 network and is surrounded by diverse landcovers as built up areas and agricultural land. Multispectral and thermal Landsat 5 satellite images of two time periods are being used. Their processing is being done by Erdas Imagine software. The general physiognomy of the area and the lake shore are examined after image enhancement techniques and image interpretation. Directions of the study concern geomorphological aspects, land covers, estimation of surface temperature as well as changes through time.

  8. Barrier effects of remote high mountain on atmospheric metal transport in the eastern Tibetan Plateau.

    Science.gov (United States)

    Bing, Haijian; Zhou, Jun; Wu, Yanhong; Luo, Xiaosan; Xiang, Zhongxiang; Sun, Hongyang; Wang, Jipeng; Zhu, He

    2018-07-01

    Anthropogenic metals adsorbed on suspended fine particles can be deposited on remote and inaccessible high mountains by long-range atmospheric transport. In this study, we investigated the cadmium (Cd) and lead (Pb) in the soils, mosses and rainfall of three transects on the Gongga Mountain, eastern Tibetan Plateau, to understand the mountain interception effects on their atmospheric transport. The concentrations of Cd and Pb in the soils and mosses displayed a pattern of eastern transect>northern transect>western transect. The distribution of Cd and Pb on the eastern transect increased from 2000 to 2900m a.s.l. (above sea level), decreased toward the timberline, and increased again with altitude; on the northern transect, it generally decreased with altitude whereas a distribution trend was not clearly observed on the western transect. The Cd and Pb concentrations in the rainfall of the eastern transect generally decreased with altitude, and they were higher inside forests than outside forests and temporally higher in the winter than the summer. The Pb isotopic ratios coupled with moss bio-monitoring distinguished anthropogenic sources of Cd and Pb on the eastern and northern transects, whereas bedrock weathering was the main source of Cd and Pb on the western transect. We proposed a conceptual model to delineate the effects of terrain, local climate and vegetation on the transport of atmospheric metals. Our results highlighted the high mountains in the eastern Tibetan Plateau as an effective natural barrier limiting atmospheric metal transport. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Carbon partitioning in the food web of a high mountain lake: from bacteria to zooplankton

    Directory of Open Access Journals (Sweden)

    Alessandra PUGNETTI

    1999-08-01

    Full Text Available The organisms of the microbial loop in Lake Paione Superiore (LPS, a high mountain lake in the Italian Alpine region, were studied together with phytoplankton and zooplankton for three successive years. The biomass of bacteria, HNF (heterotrophic nanoflagellates, ciliates and phytoplankton, as mean carbon concentration in the three years, was 30 and 37 μg C l-1 near the surface (SUR and the bottom (BOT respectively. Under the ice-cover the mean biomass carbon decreased especially at the BOT, whereas at SUR the decrease was less evident due to the maintenance of higher phytoplankton biomass (mixotrophic flagellates. In LPS ~50% of the carbon was confined in bacteria, 20% in protozoa and 30% in phytoplankton. The ratio Autotrophs/Heterotrophs was lower than 1 (mean: 0,97 at SUR and 0,58 at BOT thus indicating a system with a predominance of the heterotrophs. This might be the result of light inhibition of algal growth coupled to a production of dissolved carbon, utilized by bacteria. During late summer the peak of Daphnia longispina, the main component of the zooplankton of LPS, increased the carbon content in the lake to a total of 158 and 300 μg C l-1 in 1997 and 1998 respectively. At the late summer peaks, zooplankton represented from 78 to 89% of the total carbon of the pelagic communities. Furthermore, the presence of Daphnia could be responsible for a decrease in the biomass carbon of a variety of organisms (algae, protozoa and bacteria. It may be possible that this is an instance of zooplankton grazing on algae, protozoa and also bacteria, as Daphnia has very broad niches and may eat pico-, nanoplankton and small ciliates. In the oligotrophic LPS, a diet which also includes protozoa could give Daphnia a further chance of survival, as ciliates are an important source of fatty acids and sterols.

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

    Science.gov (United States)

    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

  11. Zonation of High Disaster Potential Communities for Remote Mountainous Areas in Southern Taiwan

    Science.gov (United States)

    Chen, Yie-Ruey; Tsai, Kuang-Jung; Chang, Chwen-Ming; Chen, Jing-Wen; Chiang, Jie-Lun; Lu, Yi-Ching; Tsai, Hui-Wen

    2017-04-01

    About three-quarters of Taiwan are covered by hillside areas. Most of the hillside regions in Taiwan are sedimentary and metamorphic rocks which are fragile and highly weathered. In recent years, human development coupled with the global impact of extreme weather, typhoons and heavy rains have caused the landslide disasters and leaded to human causalities and properties loss. The landslides also endanger the major public works and almost make the overall industrial economic development and transport path overshadowed by disasters. Therefore, this research assesses the exploration of landslide potential analysis and zonation of high disaster potential communities for remote mountainous areas in southern Taiwan. In this study, the time series of disaster records and land change of remote mountainous areas in southern Taiwan are collected using techniques of interpretation from satellite images corresponding to multi-year and multi-rainfall events. To quantify the slope hazards, we adopt statistical analysis model to analyze massive data of slope disasters and explore the variance, difference and trend of influence factors of hillside disaster; establish the disaster potential analysis model under the climate change and construct the threshold of disaster. Through analysis results of disaster potential assessment, the settlement distribution with high-risk hazard potential of study area is drawn with geographic information system. Results of image classification show that the values of coefficient of agreement for different time periods are at high level. Compared with the historical disaster records of research areas, the accuracy of predicted landslide potential is in reasonable confidence level. The spatial distribution of landslide depends on the interaction of rainfall patterns, slope and elevation of the research area. The results also show that the number and scale of secondary landslide sites are much larger than those of new landslide sites after rainfall

  12. The malacostraca Caspian Sea as object of acclimatization and enrichment of a foоd reserve of fishes of lakes, water basins of foothill and mountain Dagestan

    Directory of Open Access Journals (Sweden)

    A. A. Abdulmedzhidov

    2009-01-01

    Full Text Available Peracarilae – Paramysis (Paramysis intermedia, Paramysis (Paramysis kessleri, Paramysis (Mesomysis lacustris, Limnomysis benedeni, Niphargoides (Pontogammarus robustoides, can live in mountain lakes of Dagestan.

  13. 76 FR 41753 - Sierra National Forest, Bass Lake Ranger District, California, Grey's Mountain Ecosystem...

    Science.gov (United States)

    2011-07-15

    ..., California, Grey's Mountain Ecosystem Restoration Project AGENCY: Forest Service, USDA. ACTION: Notice of...: Background Information: The Grey's Mountain Ecosystem Restoration Project (Madera County, California) lies... vegetation. Currently, vegetation within the Grey's Mountain Ecosystem Restoration Project has changed from...

  14. Remote sensing of macrophyte morphological traits: Implications for the management of shallow lakes

    Directory of Open Access Journals (Sweden)

    Paolo Villa

    2017-03-01

    Full Text Available Macrophytes are important elements of freshwater ecosystems, fulfilling a pivotal role in biogeochemical cycles. The synoptic capabilities provided by remote sensing make it a powerful tool for monitoring aquatic vegetation characteristics and the functional status of shallow lake systems in which they occur. The latest generation of airborne and spaceborne imaging sensors can be effectively exploited for mapping morphologically – and physiologically – relevant vegetation features based on their canopy spectral response. The objectives of this study were to calibrate semi-empirical models for mapping macrophyte morphological traits (i.e., fractional cover, leaf area index and above-water biomass from hyperspectral data, and to investigate the capabilities of remote sensing in supporting macrophyte monitoring and management. We calibrated spectral models using in situ reflectance and morphological trait measures and applied them to airborne hyperspectral imaging data, acquired over two shallow European water bodies (Lake Hídvégi, in Hungary, and Mantua lakes system, in Italy in two key phenological phases. Maps of morphological traits were produced covering a broad range of aquatic plant types (submerged, floating, and emergent, common to temperate and continental regions, with an error level of 5.4% for fractional cover, 0.10 m2 m-2 for leaf area index, and 0.06 kg m-2 for above-water biomass. Based on these maps, we discuss how remote sensing could support monitoring strategies and shallow lake management with reference to our two case studies: i.e., by providing insight into spatial and species-wise variability, by assessing nutrient uptake by aquatic plants, and by identifying hotspot areas where invasive species could become a threat to ecosystem functioning and service provision.

  15. Integration of remote sensing and geochemical data in the mineral evaluation of the Yucca Mountain Addition, Nevada

    International Nuclear Information System (INIS)

    Feldman, S.C.; Castor, S.B.; Tingley, J.V.

    1996-01-01

    In 1989 the U.S. Department of Energy filed an application with the U.S. Bureau of Land Management for an administrative land withdrawal of about 4,300 acres bordering the western edge of the Nevada Test Site (NTS) and the southern edge of the Nellis Air Force Range. This area, which is referred to as the Yucca Mountain Addition, includes approximately 400 acres that are being considered as part of a potential repository for high-level nuclear waste at Yucca Mountain. A study of the geology and mineral deposits is required for a land withdrawal request under federal law. The Yucca Mountain Addition mineral evaluation was accomplished in late 1989 by field examination, sample collection, geochemical analysis, the analysis of satellite remote sensing data, and the collection of rock spectra in the field. Data from the Yucca Mountain Addition and from mining districts in the area were collected and analyzed, and the two data sets were then compared. The evaluation was limited to surficial data both at the Yucca Mountain Addition and in the mining districts. Evidence from both geochemical and remote sensing analyses indicate that the potential for mineral deposits is low in the Yucca Mountain Addition

  16. Determining the Influence of Dust on Post-Glacial Lacustrine Sedimentation in Bald Lake, Uinta Mountains, Utah

    Science.gov (United States)

    O'Keefe, S. S.; McElroy, R.; Munroe, J. S.

    2016-12-01

    Dust is increasingly recognized as an important component of biogeochemical cycling and ecosystem function in mountain environments. Previous work has shown that delivery of dust to the Uinta Mountains of northeastern Utah has influenced pedogenesis, soil nutrient status, and surface water chemistry. An array of passive and active samplers in the alpine zone of the Uintas provides detailed information about contemporary dust fluxes, along with physical and geochemical properties of modern dust. Reconstruction of changes in the dust system over time, however, requires continuous sedimentary archives sensitive to dust inputs. A radiocarbon-dated 3.5-m core (spanning 12.7 kyr) collected from subalpine Bald Lake may provide such a record. Passive dust collectors in the vicinity of the lake constrain the geochemical properties of modern dust, whereas samples of regolith constrain properties of the local surficial material within the watershed. Together, these represent two end member sources of clastic sediment to Bald Lake basin: allochthonous dust and autochthonous regolith. Ba and Eu are found in higher abundances in the dust than in the watershed regolith. Zr and Th are found to be lower in the dust than in the watershed. Geochemical analysis of the sediment core allows the relative contribution of exotic and local material to the lake to be considered as a time series covering the post-glacial interval when indicator elements are plotted. Findings suggest Bald Lake's dust record tracks regional aridity and corresponds to low-stands of large lakes in the southwestern United States. Spatial variability of elemental abundances in the watershed suggests there are more than two input sources contributing to the lake over time.

  17. Lake Storage Measurements For Water Resources Management: Combining Remotely Sensed Water Levels and Surface Areas

    Science.gov (United States)

    Brakenridge, G. R.; Birkett, C. M.

    2013-12-01

    Presently operating satellite-based radar altimeters have the ability to monitor variations in surface water height for large lakes and reservoirs, and future sensors will expand observational capabilities to many smaller water bodies. Such remote sensing provides objective, independent information where in situ data are lacking or access is restricted. A USDA/NASA (http://www.pecad.fas.usda.gov/cropexplorer/global_reservoir/) program is performing operational altimetric monitoring of the largest lakes and reservoirs around the world using data from the NASA/CNES, NRL, and ESA missions. Public lake-level products from the Global Reservoir and Lake Monitor (GRLM) are a combination of archived and near real time information. The USDA/FAS utilizes the products for assessing international irrigation potential and for crop production estimates; other end-users study climate trends, observe anthropogenic effects, and/or are are involved in other water resources management and regional water security issues. At the same time, the Dartmouth Flood Observatory (http://floodobservatory.colorado.edu/), its NASA GSFC partners (http://oas.gsfc.nasa.gov/floodmap/home.html), and associated MODIS data and automated processing algorithms are providing public access to a growing GIS record of the Earth's changing surface water extent, including changes related to floods and droughts. The Observatory's web site also provide both archival and near real time information, and is based mainly on the highest spatial resolution (250 m) MODIS bands. Therefore, it is now possible to provide on an international basis reservoir and lake storage change measurements entirely from remote sensing, on a frequently updating basis. The volume change values are based on standard numerical procedures used for many decades for analysis of coeval lake area and height data. We provide first results of this combination, including prototype displays for public access and data retrieval of water storage

  18. A Remote Sensing Approach to Estimate Vertical Profile Classes of Phytoplankton in a Eutrophic Lake

    Directory of Open Access Journals (Sweden)

    Kun Xue

    2015-10-01

    Full Text Available The extension and frequency of algal blooms in surface waters can be monitored using remote sensing techniques, yet knowledge of their vertical distribution is fundamental to determine total phytoplankton biomass and understanding temporal variability of surface conditions and the underwater light field. However, different vertical distribution classes of phytoplankton may occur in complex inland lakes. Identification of the vertical profile classes of phytoplankton becomes the key and first step to estimate its vertical profile. The vertical distribution profile of phytoplankton is based on a weighted integral of reflected light from all depths and is difficult to determine by reflectance data alone. In this study, four Chla vertical profile classes (vertically uniform, Gaussian, exponential and hyperbolic were found to occur in three in situ vertical surveys (28 May, 19–24 July and 10–12 October in a shallow eutrophic lake, Lake Chaohu. We developed and validated a classification and regression tree (CART to determine vertical phytoplankton biomass profile classes. This was based on an algal bloom index (Normalized Difference algal Bloom Index, NDBI applied to both in situ remote sensing reflectance (Rrs and MODIS Rayleigh-corrected reflectance (Rrc data in combination with data of local wind speed. The results show the potential of retrieving Chla vertical profiles information from integrated information sources following a decision tree approach.

  19. Mountains

    Science.gov (United States)

    Regina M. Rochefort; Laurie L. Kurth; Tara W. Carolin; Robert R. Mierendorf; Kimberly Frappier; David L. Steenson

    2006-01-01

    This chapter concentrates on subalpine parklands and alpine meadows of southern British Columbia, Washington, Oregon, and western Montana. These areas lie on the flanks of several mountain ranges including the Olympics, the Cascades of Oregon and Washington, and the Coast Mountains in British Columbia.

  20. Eradication of non-native fish from a small mountain lake: gill netting as a non-toxic alternative to the use of rotenone.

    Science.gov (United States)

    R.A. Knapp; K.R. Matthews

    1998-01-01

    Nearly all mountain lakes in the western United States were historically fishless, but most now contain introduced trout populations. As a result of the impacts of these introductions on ecosystem structure and function, there is increasing interest in restoring some lakes to a fishless condition. To date, however, the only effective method of fish eradication is the...

  1. Community-based Monitoring of Water Resources in Remote Mountain Regions

    Science.gov (United States)

    Buytaert, W.; Hannah, D. M.; Dewulf, A.; Clark, J.; Zulkafli, Z. D.; Karpouzoglou, T.; Mao, F.; Ochoa-Tocachi, B. F.

    2016-12-01

    Remote mountain regions are often represented by pockets of poverty combined with accelerated environmental change. The combination of harsh climatic and topographical conditions with limited infrastructure puts severe pressures on local livelihoods, many of which rely strongly on local ecosystem services (ESS) such as agricultural production and water supply. It is therefore paramount to optimise the management of ESS for the benefit of local people. This is hindered by a scarcity of quantitative data about physical processes such as precipitation and river flow as well as qualitative data concerning the management of water and land. National and conventional scientific monitoring networks tend to be insufficient to cover adequately the spatial and temporal gradients. Additionally, the data that are being collected often fail to be converted into locally relevant and actionable knowledge for ESS management. In such conditions, community-based monitoring of natural resources may be an effective way to reduce this knowledge gap. The participatory nature of such monitoring also enhances knowledge co-production and integration in locally-based decision-making processes. Here, we present the results of a 4-year consortium project on the use of citizen science technologies for ecosystem services management (Mountain-EVO). The project analyzed ecosystem service dynamics and decision-making processes and implemented a comparative analysis of experiments with community-based monitoring of water resources in 4 remote mountain regions, i.e. Peru, Nepal, Kyrgyzstan, and Ethiopia. We find that community-based monitoring can have a transformative impact on local ESS management, because of its potential to be more inclusive, polycentric, and context-driven as compared to conventional monitoring. However, the results and effectiveness of community-based approaches depend strongly on the natural and socio-economic boundary conditions. As such, this requires a tailored and bottom

  2. Eye problems in mountain and remote areas: prevention and onsite treatment--official recommendations of the International Commission for Mountain Emergency Medicine ICAR MEDCOM.

    Science.gov (United States)

    Ellerton, John A; Zuljan, Igor; Agazzi, Giancelso; Boyd, Jeffrey J

    2009-01-01

    Although eyes are not frequently injured in the mountains, they are exposed to many adverse factors from the environment. This article, intended for first responders, paramedics, physicians, and mountaineers, is the consensus opinion of the International Commission for Mountain Emergency Medicine (ICAR-MEDCOM). Its aim is to give practical advice on the management of eye problems in mountainous and remote areas. Snow blindness and minor injuries, such as conjunctival and corneal foreign bodies, could immobilize a person and put him or her at risk of other injuries. Blunt or penetrating trauma can result in the loss of sight in the eye; this may be preventable if the injury is managed properly. In almost all cases of severe eye trauma, protecting the eye and arranging an immediate evacuation are necessary. The most common eye problems, however, are due to ultraviolet light and high altitude. People wearing contact lenses and with previous history of eye diseases are more vulnerable. Any sight-threatening eye problem or unexplained visual loss at high altitude necessitates descent. Wearing appropriate eye protection, such as sunglasses with sidepieces and goggles with polarized or photochromic lenses, could prevent most of the common eye problems in mountaineering.

  3. Modeling the Hydrological Regime of Turkana Lake (Kenya, Ethiopia) by Combining Spatially Distributed Hydrological Modeling and Remote Sensing Datasets

    Science.gov (United States)

    Anghileri, D.; Kaelin, A.; Peleg, N.; Fatichi, S.; Molnar, P.; Roques, C.; Longuevergne, L.; Burlando, P.

    2017-12-01

    Hydrological modeling in poorly gauged basins can benefit from the use of remote sensing datasets although there are challenges associated with the mismatch in spatial and temporal scales between catchment scale hydrological models and remote sensing products. We model the hydrological processes and long-term water budget of the Lake Turkana catchment, a transboundary basin between Kenya and Ethiopia, by integrating several remote sensing products into a spatially distributed and physically explicit model, Topkapi-ETH. Lake Turkana is the world largest desert lake draining a catchment of 145'500 km2. It has three main contributing rivers: the Omo river, which contributes most of the annual lake inflow, the Turkwel river, and the Kerio rivers, which contribute the remaining part. The lake levels have shown great variations in the last decades due to long-term climate fluctuations and the regulation of three reservoirs, Gibe I, II, and III, which significantly alter the hydrological seasonality. Another large reservoir is planned and may be built in the next decade, generating concerns about the fate of Lake Turkana in the long run because of this additional anthropogenic pressure and increasing evaporation driven by climate change. We consider different remote sensing datasets, i.e., TRMM-V7 for precipitation, MERRA-2 for temperature, as inputs to the spatially distributed hydrological model. We validate the simulation results with other remote sensing datasets, i.e., GRACE for total water storage anomalies, GLDAS-NOAH for soil moisture, ERA-Interim/Land for surface runoff, and TOPEX/Poseidon for satellite altimetry data. Results highlight how different remote sensing products can be integrated into a hydrological modeling framework accounting for their relative uncertainties. We also carried out simulations with the artificial reservoirs planned in the north part of the catchment and without any reservoirs, to assess their impacts on the catchment hydrological

  4. Remote and terrestrial ground monitoring techniques integration for hazard assessment in mountain areas

    Science.gov (United States)

    Chinellato, Giulia; Kenner, Robert; Iasio, Christian; Mair, Volkmar; Mosna, David; Mulas, Marco; Phillips, Marcia; Strada, Claudia; Zischg, Andreas

    2014-05-01

    In high mountain regions the choice of appropriate sites for infrastructure such as roads, railways, cable cars or hydropower dams is often very limited. In parallel, the increasing demand for supply infrastructure in the Alps induces a continuous transformation of the territory. The new role played by the precautionary monitoring in the risk governance becomes fundamental and may overcome the modeling of future events, which represented so far the predominant approach to these sort of issues. Furthermore the consequence of considering methodologies alternative to those more exclusive allow to reduce costs and increasing the frequency of measurements, updating continuously the cognitive framework of existing hazard condition in most susceptible territories. The scale factor of the observed area and the multiple purpose of such regional ordinary surveys make it convenient to adopt Radar Satellite-based systems, but they need to be integrated with terrestrial systems for validation and eventual early warning purposes. Significant progress over the past decade in Remote Sensing (RS), Proximal Sensing and integration-based sensor networks systems now provide technologies, that allow to implement monitoring systems for ordinary surveys of extensive areas or regions, which are affected by active natural processes and slope instability. The Interreg project SloMove aims to provide solutions for such challenges and focuses on using remote sensing monitoring techniques for the monitoring of mass movements in two test sites, in South Tyrol (Italy) and in Grisons Canton (Switzerland). The topics faced in this project concern mass movements and slope deformation monitoring techniques, focusing mainly on the integration of multi-temporal interferometry, new generation of terrestrial technologies for differential digital terrain model elaboration provided by laser scanner (TLS), and GNSS-based topographic surveys, which are used not only for validation purpose, but also for

  5. Increasing risks related to landslides from degrading permafrost into new lakes in de-glaciating mountain ranges

    Science.gov (United States)

    Haeberli, Wilfried; Schaub, Yvonne; Huggel, Christian

    2017-09-01

    While glacier volumes in most cold mountain ranges rapidly decrease due to continued global warming, degradation of permafrost at altitudes above and below glaciers is much slower. As a consequence, many still existing glacier and permafrost landscapes probably transform within decades into new landscapes of bare bedrock, loose debris, sparse vegetation, numerous new lakes and steep slopes with slowly degrading permafrost. These new landscapes are likely to persist for centuries if not millennia to come. During variable but mostly extended future time periods, such new landscapes will be characterized by pronounced disequilibria within their geo- and ecosystems. This especially involves long-term stability reduction of steep/icy mountain slopes as a slow and delayed reaction to stress redistribution following de-buttressing by vanishing glaciers and to changes in mechanical strength and hydraulic permeability caused by permafrost degradation. Thereby, the probability of far-reaching flood waves from large mass movements into lakes systematically increases with the formation of many new lakes and systems of lakes in close neighborhood to, or even directly at the foot of, so-affected slopes. Results of recent studies in the Swiss Alps are reviewed and complemented with examples from the Cordillera Blanca in Peru and the Mount Everest region in Nepal. Hot spots of future hazards from potential flood waves caused by large rock falls into new lakes can already now be recognized. To this end, integrated spatial information on glacier/permafrost evolution and lake formation can be used together with scenario-based models for rapid mass movements, impact waves and flood propagation. The resulting information must then be combined with exposure and vulnerability considerations related to settlements and infrastructure. This enables timely planning of risk reduction options. Such risk reduction options consist of two components: Mitigation of hazards, which in the present

  6. Cholera in the Lake Kivu region (DRC): Integrating remote sensing and spatially explicit epidemiological modeling

    Science.gov (United States)

    Finger, Flavio; Knox, Allyn; Bertuzzo, Enrico; Mari, Lorenzo; Bompangue, Didier; Gatto, Marino; Rodriguez-Iturbe, Ignacio; Rinaldo, Andrea

    2014-07-01

    Mathematical models of cholera dynamics can not only help in identifying environmental drivers and processes that influence disease transmission, but may also represent valuable tools for the prediction of the epidemiological patterns in time and space as well as for the allocation of health care resources. Cholera outbreaks have been reported in the Democratic Republic of the Congo since the 1970s. They have been ravaging the shore of Lake Kivu in the east of the country repeatedly during the last decades. Here we employ a spatially explicit, inhomogeneous Markov chain model to describe cholera incidence in eight health zones on the shore of the lake. Remotely sensed data sets of chlorophyll a concentration in the lake, precipitation and indices of global climate anomalies are used as environmental drivers in addition to baseline seasonality. The effect of human mobility is also modelled mechanistically. We test several models on a multiyear data set of reported cholera cases. The best fourteen models, accounting for different environmental drivers, and selected using the Akaike information criterion, are formally compared via proper cross validation. Among these, the one accounting for seasonality, El Niño Southern Oscillation, precipitation and human mobility outperforms the others in cross validation. Some drivers (such as human mobility and rainfall) are retained only by a few models, possibly indicating that the mechanisms through which they influence cholera dynamics in the area will have to be investigated further.

  7. Dynamics Change of Honghu Lake's Water Surface Area and Its Driving Force Analysis Based on Remote Sensing Technique and TOPMODEL model

    International Nuclear Information System (INIS)

    Wen, X; Cao, B; Shen, S; Hu, D; Tang, X

    2014-01-01

    Honghu Lake is the largest freshwater lake in the Hubei Province of China. This paper introduces a remote sensing approach to monitor the lake's water surface area dynamics over the last 40 years by using multi-temporal remote sensing imagery including Landsat and HJ-1. Meanwhile, the daily precipitation and evaporation data provided by Honghu meteorological station since 1970s were also collected and used to analyze the influence of climate change factors. The typical situation for precipitation was selected as an input into the TOPMODEL model to simulate the hydrological process in Honghu Lake. The simulation result with the water surface area extracted from remote sensing imagery was analyzed. This experiment shows the precipitation and timing of precipitation effects changes in the lake with remote sensing data and it showed the potential of using TOPMODEL model to analyze the combined hydrological process in Honghu Lake

  8. Lake acidification in the Adirondack Mountains of New York causes and consequences

    Science.gov (United States)

    Carl L. Schofield

    1976-01-01

    Current and historic geographic distributions of acidity in Adirondack lakes were examined in relation to regional edaphic, climatic, and physiographic features. Acid conditions are currently predominant in high elevation drainage lakes having small watershed/surface area ratios. Comparable levels of acidity were found only in small seepage lakes and bog ponds during...

  9. Holocene vegetation dynamics of Taiga forest in the Southern Altai Mountains documented by sediments from Kanas Lake

    Science.gov (United States)

    Huang, X.; Chen, F.

    2016-12-01

    The Chinese Altai is the southern limit of the Taiga forest of the continent, and regional vegetation dynamics during the Holocene will help us to understand regional climate changes, such as the Siberian High variations. Here we present a pollen-based vegetation and climate reconstruction from a well dated sediment core from Kanas Lake, a deep glacial moraine dammed lake in the Southern Altai Mountains (Chinese Altai). The 244-cm-long sequence spans the last 13,500 years, and the chronology is based on nine accelerator mass spectrometry radiocarbon dates from terrestrial plant macrofossils. At least five stages of regional vegetation history are documented: (i) From 13.5 to 11.7 ka (1 ka = 1000 cal yr BP), Kanas Lake region was occupied by steppe dominated by Artemisia, Chenopodiaceae and grass pollen, with low tree coverage. (ii) From 11.7 to 8.5 ka, regional forest build up dramatically indicated by increasing tree pollen percentages, including Picea, Larix, and the highest Junipers, with decreasing Artemisia and increasing Chenopodiaceae. (iii) From 8.5 to 7.2 ka, the forest around the lake became dense with the maximum content of Picea and Betula pollen types. And the steppe pollen types reached their lowest values. (iv) From 7.2 to 4 ka, as a typical tree species of Taiga forest, Larix pollen percentage became much higher than previous stage, and the sum of trees & shrubs pollen types decreased, which possibly indicated cooler and wetter climate (v) After 4 ka, trees & shrubs (e.g. Betula, Junipers) pollen types decreased, with increasing Artemisia and decreasing Chenopodiaceae, which might indicated more humid and cooler climate in the late Holocene. Comparing to the other pollen records in the Altai Mountains, Lake Grusha and Lake Hoton had recorded a slightly different process of vegetation evolution in the early Holocene, where forest was built up in the northern side of the Chinese Altai faster than that of the Kanas Lake area. And the difference could

  10. Huguangyan Maar Lake (SE China): A solid record of atmospheric mercury pollution history in a non-remote region

    Science.gov (United States)

    Zeng, Yan; Chen, Jingan; Yang, Yongqiong; Wang, Jianxu; Zhu, Zhengjie; Li, Jian

    2017-10-01

    Mercury is a highly toxic metal that can cause harm to environment and human health. As atmospheric deposition is the main source of total Hg input to aquatic system in remote and pristine regions, almost all the studies on atmospheric Hg pollution history concentrated in these areas, while the studies in non-remote areas are much limited, especially for the long history records. In this study, Huguangyan Maar Lake, an undisturbed lake system at low altitude in China, was selected to reconstruct the atmospheric mercury pollution history. Variation patterns of TOC, Hg and non-residual Sr in the sediment core indicated that, compared to the direct atmospheric Hg deposition, the effect of either Hg scavenging from water column by algae or the catchment inputs of previously deposited Hg on the Hg accumulation in the lake sediment was limited. The sediment Hg content in Huguangyan Lake was mainly controlled by the atmospheric Hg deposition, and thus accurately reflected the atmospheric Hg pollution history. The Hga (Hg content from atmospheric deposition) in Huguangyan Lake presented a comparable variation pattern to that in remote sites. It had the same variation trend as the global atmospheric Hg before 1950 CE, which could be attributed to the Industrial Revolution. After that, it was mainly controlled by Hg emissions from Asian countries. The variation of Hga also indicated that atmospheric Hg deposition accelerated significantly since 2000 CE. This study, along with other investigations in remote sites in China, showed that the sediment Hg in Huguangyan Lake responded to the atmospheric Hg pollution more sensitively than in the alpine regions. It should be noted that, the more intensive acceleration of Hg deposition in Huguangyan Lake may imply that the South of China suffered from much more serious atmospheric Hg pollution than previous studies revealed.

  11. Monitoring the Fluctuation of Lake Qinghai Using Multi-Source Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Wenbin Zhu

    2014-10-01

    Full Text Available The knowledge of water storage variations in ungauged lakes is of fundamental importance to understanding the water balance on the Tibetan Plateau. In this paper, a simple framework was presented to monitor the fluctuation of inland water bodies by the combination of satellite altimetry measurements and optical satellite imagery without any in situ measurements. The fluctuation of water level, surface area, and water storage variations in Lake Qinghai were estimated to demonstrate this framework. Water levels retrieved from ICESat (Ice, Cloud, and and Elevation Satellite elevation data and lake surface area derived from MODIS (Moderate Resolution Imaging Spectroradiometer product were fitted by linear regression during the period from 2003 to 2009 when the overpass time for both of them was coincident. Based on this relationship, the time series of water levels from 1999 to 2002 were extended by using the water surface area extracted from Landsat TM/ETM+ images as inputs, and finally the variations of water volume in Lake Qinghai were estimated from 1999 to 2009. The overall errors of water levels retrieved by the simple method in our work were comparable with other globally available test results with r = 0.93, MAE = 0.07 m, and RMSE = 0.09 m. The annual average rate of increase was 0.11 m/yr, which was very close to the results obtained from in situ measurements. High accuracy was obtained in the estimation of surface areas. The MAE and RMSE were only 6 km2, and 8 km2, respectively, which were even lower than the MAE and RMAE of surface area extracted from Landsat TM images. The estimated water volume variations effectively captured the trend of annual variation of Lake Qinghai. Good agreement was achieved between the estimated and measured water volume variations with MAE = 0.4 billion m3, and RMSE = 0.5 billion m3, which only account for 0.7% of the total water volume of Lake Qinghai. This study demonstrates that it is feasible to monitor

  12. Remote Sensing of Black Lakes and Using 810 nm Reflectance Peak for Retrieving Water Quality Parameters of Optically Complex Waters

    Directory of Open Access Journals (Sweden)

    Tiit Kutser

    2016-06-01

    Full Text Available Many lakes in boreal and arctic regions have high concentrations of CDOM (coloured dissolved organic matter. Remote sensing of such lakes is complicated due to very low water leaving signals. There are extreme (black lakes where the water reflectance values are negligible in almost entire visible part of spectrum (400–700 nm due to the absorption by CDOM. In these lakes, the only water-leaving signal detectable by remote sensing sensors occurs as two peaks—near 710 nm and 810 nm. The first peak has been widely used in remote sensing of eutrophic waters for more than two decades. We show on the example of field radiometry data collected in Estonian and Swedish lakes that the height of the 810 nm peak can also be used in retrieving water constituents from remote sensing data. This is important especially in black lakes where the height of the 710 nm peak is still affected by CDOM. We have shown that the 810 nm peak can be used also in remote sensing of a wide variety of lakes. The 810 nm peak is caused by combined effect of slight decrease in absorption by water molecules and backscattering from particulate material in the water. Phytoplankton was the dominant particulate material in most of the studied lakes. Therefore, the height of the 810 peak was in good correlation with all proxies of phytoplankton biomass—chlorophyll-a (R2 = 0.77, total suspended matter (R2 = 0.70, and suspended particulate organic matter (R2 = 0.68. There was no correlation between the peak height and the suspended particulate inorganic matter. Satellite sensors with sufficient spatial and radiometric resolution for mapping lake water quality (Landsat 8 OLI and Sentinel-2 MSI were launched recently. In order to test whether these satellites can capture the 810 nm peak we simulated the spectral performance of these two satellites from field radiometry data. Actual satellite imagery from a black lake was also used to study whether these sensors can detect the peak

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

    Science.gov (United States)

    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

  14. Study on Net Primary Productivity over Complicated Mountainous Area based on Multi-Source Remote Sensing Data

    Science.gov (United States)

    Guan, X.; Shen, H.; Li, X.; Gan, W.

    2017-12-01

    Mountainous area hosts approximately a quarter of the global land surface, with complex climate and ecosystem conditions. More knowledge about mountainous ecosystem could highly advance our understanding of the global carbon cycle and climate change. Net Primary Productivity (NPP), the biomass increment of plants, is a widely used ecological indicator that can be obtained by remote sensing methods. However, limited by the defective characteristic of sensors, which cannot be long-term with enough spatial details synchronously, the mountainous NPP was far from being understood. In this study, a multi-sensor fusion framework was applied to synthesize a 1-km NPP series from 1982 to 2014 in mountainous southwest China, where elevation ranged from 76m to 6740m. The validation with field-measurements proved this framework greatly improved the accuracy of NPP (r=0.79, prun-off. What is more, it was indicated that the NPP variation showed three distinct stages at the year break-point of 1992 and 2002 over the region. The NPP in low-elevation area varied almost triple more drastic than the high-elevation area for all the three stages, due to the much greater change rate of precipitation. In summary, this study innovatively conducted a long-term and accurate NPP study on the not understood mountainous ecosystem with multi-source data, the framework and conclusions will be beneficial for the further cognition of global climate change.

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

    Science.gov (United States)

    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.

  16. Thermal Remote Sensing of Lava Lakes on Io and Earth (Invited)

    Science.gov (United States)

    Davies, A. G.; Keszthelyi, L. P.; McEwen, A. S.

    2013-12-01

    Volcanology has been transformed by remote sensing. For decades, Earth's volcanoes have been studied in the infrared by a wide variety of instruments on spacecraft at widely varying spectral, spatial and temporal resolutions, for which techniques have been developed to interpret and understand ongoing volcanic eruptions. The study of volcanism on Io, the only Solar System body besides Earth known to have ongoing, high temperature, silicate-based effusive and explosive volcanic eruptions, requires new remote sensing techniques. The extraordinary volcanism allows us to examine Io's interior and composition from the material erupted onto the surface. For Io, the biggest question in the wake of NASA's Galileo mission concerns the eruption temperature of Io's dominant silicate lavas [1,2]. Constraining eruption temperature constrains magma composition, in turn a reflection of the composition, physical state and tidal heating within Io. However, the extraction of lava eruption temperature from remote sensing data is difficult. Detector saturation is likely except when the hot material fills a tiny fraction of a resolution element, unless instruments are designed for this objective. High temperature lava surfaces cool rapidly, so remote observations can miss the peak temperature. Observations at different wavelengths must be acquired nearly simultaneously to derive accurate temperatures of very hot and dynamic sources [3]. Uncertainties regarding hot lava emissivity [4] also reduce the confidence in derived temperatures. From studying thermal emission data from different styles of volcanic activity on Earth by remote sensing in conjunction with contemporaneous observations on the ground, it is found that only certain styles of volcanic activity are suitable for deriving liquid lava temperatures [3]. Active lava lakes are particularly useful, especially during a phase of lava fountaining. Examination and analysis of FLIR data obtained at the Erta'Ale (Ethiopia) basaltic

  17. Regional-scale analysis of lake outburst hazards in the southwestern Pamir, Tajikistan, based on remote sensing and GIS

    Directory of Open Access Journals (Sweden)

    M. Mergili

    2011-05-01

    Full Text Available This paper presents an analysis of the hazards emanating from the sudden drainage of alpine lakes in South-Western Tajik Pamir. In the last 40 yr, several new lakes have formed in the front of retreating glacier tongues, and existing lakes have grown. Other lakes are dammed by landslide deposits or older moraines. In 2002, sudden drainage of a glacial lake in the area triggered a catastrophic debris flow. Building on existing approaches, a rating scheme was devised allowing quick, regional-scale identification of potentially hazardous lakes and possible impact areas. This approach relies on GIS, remote sensing and empirical modelling, largely based on medium-resolution international datasets. Out of the 428 lakes mapped in the area, 6 were rated very hazardous and 34 hazardous. This classification was used for the selection of lakes requiring in-depth investigation. Selected cases are presented and discussed in order to understand the potentials and limitations of the approach used. Such an understanding is essential for the appropriate application of the methodology for risk mitigation purposes.

  18. Integrated Application of Remote Sensing, GIS and Hydrological Modeling to Estimate the Potential Impact Area of Earthquake-Induced Dammed Lakes

    OpenAIRE

    Bo Cao; Shengmei Yang; Song Ye

    2017-01-01

    Dammed lakes are an important secondary hazard caused by earthquakes. They can induce further damage to nearby humans. Current hydrology calculation research on dammed lakes usually lacks spatial expressive ability and cannot accurately conduct impact assessment without the support of remote sensing, which obtains important characteristic information of dammed lakes. The current study aims to address the issues of the potential impact area estimate of earthquake-induced dammed lakes by combin...

  19. Shifting mountain snow patterns in a changing climate from remote sensing retrieval.

    Science.gov (United States)

    Dedieu, J P; Lessard-Fontaine, A; Ravazzani, G; Cremonese, E; Shalpykova, G; Beniston, M

    2014-09-15

    Observed climate change has already led to a wide range of impacts on environmental systems and society. In this context, many mountain regions seem to be particularly sensitive to a changing climate, through increases in temperature coupled with changes in precipitation regimes that are often larger than the global average (EEA, 2012). In mid-latitude mountains, these driving factors strongly influence the variability of the mountain snow-pack, through a decrease in seasonal reserves and earlier melting of the snow pack. These in turn impact on hydrological systems in different watersheds and, ultimately, have consequences for water management. Snow monitoring from remote sensing provides a unique opportunity to address the question of snow cover regime changes at the regional scale. This study outlines the results retrieved from the MODIS satellite images over a time period of 10 hydrological years (2000-2010) and applied to two case studies of the EU FP7 ACQWA project, namely the upper Rhone and Po in Europe and the headwaters of the Syr Darya in Kyrgyzstan (Central Asia). The satellite data were provided by the MODIS Terra MOD-09 reflectance images (NASA) and MOD-10 snow products (NSIDC). Daily snow maps were retrieved over that decade and the results presented here focus on the temporal and spatial changes in snow cover. This paper highlights the statistical bias observed in some specific regions, expressed by the standard deviation values (STD) of annual snow duration. This bias is linked to the response of snow cover to changes in elevation and can be used as a signal of strong instability in regions sensitive to climate change: with alternations of heavy snowfalls and rapid snow melting processes. The interest of the study is to compare the methodology between the medium scales (Europe) and the large scales (Central Asia) in order to overcome the limits of the applied methodologies and to improve their performances. Results show that the yearly snow cover

  20. An inventory of historical glacial lake outburst floods in the Himalayas based on remote sensing observations and geomorphological analysis

    Science.gov (United States)

    Nie, Yong; Liu, Qiao; Wang, Jida; Zhang, Yili; Sheng, Yongwei; Liu, Shiyin

    2018-05-01

    Glacial lake outburst floods (GLOFs) are a unique type of natural hazard in the cryosphere that may result in catastrophic fatalities and damages. The Himalayas are known as one of the world's most GLOF-vulnerable zones. Effective hazard assessments and risk management require a thorough inventory of historical GLOF events across the Himalayas, which is hitherto absent. Existing studies imply that numerous historical GLOF events are contentious because of discrepant geographic coordinates, names, or outburst time, requiring further verifications. This study reviews and verifies over 60 historical GLOF events across the Himalayas using a comprehensive method that combines literature documentations, archival remote sensing observations, geomorphological analysis, and field investigations. As a result, three unreported GLOF events were discovered from remote sensing images and geomorphological analysis. Eleven suspicious events were identified and suggested to be excluded. The properties of five outburst lakes, i.e., Degaco, Chongbaxia Tsho, Geiqu, Lemthang Tsho, and a lake on Tshojo Glacier, were corrected or updated. A total of 51 GLOF events were verified to be convincing, and these outburst lakes were classified into three categories according to their statuses in the past decades, namely disappeared (12), stable (30), and expanding (9). Statistics of the verified GLOF events show that GLOF tended to occur between April and October in the Himalayas. We suggest that more attention should be paid to rapidly expanding glacial lakes with high possibility of repetitive outbursts. This study also demonstrates the effectiveness of integrating remote sensing and geomorphic interpretations in identifying and verifying GLOF events in remote alpine environments. This inventory of GLOFs with a range of critical attributes (e.g., locations, time, and mechanisms) will benefit the continuous monitoring and prediction of potentially dangerous glacial lakes and contribute to

  1. Changes in precipitating snow chemistry with seasonality in the remote Laohugou glacier basin, western Qilian Mountains.

    Science.gov (United States)

    Dong, Zhiwen; Qin, Dahe; Qin, Xiang; Cui, Jianyong; Kang, Shichang

    2017-04-01

    Trace elements in the atmosphere could provide information about regional atmospheric pollution. This study presented a whole year of precipitation observation data regarding the concentrations of trace metals (e.g., Cr, Ni, Cu, Mn, Cd, Mo, Pb, Sb, Ti, and Zn), and a TEM-EDX (transmission electron microscope-energy dispersive X-ray spectrometer) analysis from June 2014 to September 2015 at a remote alpine glacier basin in Northwest China, the Laohugou (LHG) basin (4200 m a.s.l.), to determine the regional scale of atmospheric conditions and chemical processing in the free troposphere in the region. The results of the concentrations of trace metals showed that, although the concentrations generally were lower compared with that of surrounding rural areas (and cities), they showed an obviously higher concentration and higher EFs in winter (DJF) and a relatively lower concentration and lower EFs in summer (JJA) and autumn (SON), implying clearly enhanced winter pollution of the regional atmosphere in Northwest China. The TEM observed residue in precipitation that was mainly composed of types of dust, salt-dust, BC-fly ash-soot, and organic particles in precipitation, which also showed remarked seasonal change, showing an especially high ratio of BC-soot-fly ash particles in winter precipitation compared with that of other seasons (while organic particles were higher in the summer), indicating significant increased anthropogenic particles in the winter atmosphere. The source of increased winter anthropogenic pollutants mainly originated from emissions from coal combustion, e.g., the regional winter heating supply for residents and cement factories in urban and rural regions of Northwest China. Moderate Resolution Imaging Spectroradiometer (MODIS) atmospheric optical depth (AOD) also showed a significant influence of regional atmospheric pollutant emissions over the region in winter. In total, this work indicated that the atmospheric environment in western Qilian

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

    Science.gov (United States)

    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). Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Developing the remote sensing-based early warning system for monitoring TSS concentrations in Lake Mead.

    Science.gov (United States)

    Imen, Sanaz; Chang, Ni-Bin; Yang, Y Jeffrey

    2015-09-01

    Adjustment of the water treatment process to changes in water quality is a focus area for engineers and managers of water treatment plants. The desired and preferred capability depends on timely and quantitative knowledge of water quality monitoring in terms of total suspended solids (TSS) concentrations. This paper presents the development of a suite of nowcasting and forecasting methods by using high-resolution remote-sensing-based monitoring techniques on a daily basis. First, the integrated data fusion and mining (IDFM) technique was applied to develop a near real-time monitoring system for daily nowcasting of the TSS concentrations. Then a nonlinear autoregressive neural network with external input (NARXNET) model was selected and applied for forecasting analysis of the changes in TSS concentrations over time on a rolling basis onward using the IDFM technique. The implementation of such an integrated forecasting and nowcasting approach was assessed by a case study at Lake Mead hosting the water intake for Las Vegas, Nevada, in the water-stressed western U.S. Long-term monthly averaged results showed no simultaneous impact from forest fire events on accelerating the rise of TSS concentration. However, the results showed a probable impact of a decade of drought on increasing TSS concentration in the Colorado River Arm and Overton Arm. Results of the forecasting model highlight the reservoir water level as a significant parameter in predicting TSS in Lake Mead. In addition, the R-squared value of 0.98 and the root mean square error of 0.5 between the observed and predicted TSS values demonstrates the reliability and application potential of this remote sensing-based early warning system in terms of TSS projections at a drinking water intake. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. High-mountain lakes provide a seasonal niche for migrant American dippers

    Science.gov (United States)

    J. M. Garwood; K. L. Pope; R. M. Bourque; M. D. Larson

    2009-01-01

    We studied summer use of high elevation lakes by American Dippers (Cinclus mexicanus) in the Trinity Alps Wilderness, California by conducting repeated point-count surveys at 16 study lakes coupled with a 5-year detailed survey of all available aquatic habitats in a single basin. We observed American Dippers during 36% of the point-count surveys...

  5. Assessing Climate-Induced Change in River Flow Using Satellite Remote Sensing and Process Modeling in High Mountain Asia

    Science.gov (United States)

    McDonald, K. C.

    2017-12-01

    Snow- and glacier-fed river systems originating from High Mountain Asia (HMA) support diverse ecosystems and provide the basis for food and energy production for more than a billion people living downstream. Climate-driven changes in the melting of snow and glaciers and in precipitation patterns are expected to significantly alter the flow of the rivers in the HMA region at various temporal scales, which in turn could heavily affect the socioeconomics of the region. Hence, climate change effects on seasonal and long-term hydrological conditions may have far reaching economic impact annually and over the century. We are developing a decision support tool utilizing integrated microwave remote sensing datasets, process modeling and economic models to inform water resource management decisions and ecosystem sustainability as related to the High Mountain Asia (HMA) region's response to climate change. The availability of consistent time-series microwave remote sensing datasets from Earth-orbiting scatterometers, radiometers and synthetic aperture radar (SAR) imagery provides the basis for the observational framework of this monitoring system. We discuss the assembly, processing and application of scatterometer and SAR data sets from the Advanced Scatterometer (ASCAT) and Sentinal-1 SARs, and the enlistment of these data to monitor seasonal melt and thaw status of glacier-dominated and surrounding regions. We present current status and future plans for this effort. Our team's study emphasizes processes and economic modeling within the Trishuli basin; our remote sensing analysis supports analyses across the HiMAT domain.

  6. A Functional Approach to Zooplankton Communities in Mountain Lakes Stocked With Non-Native Sportfish Under a Changing Climate

    Science.gov (United States)

    Redmond, Laura E.; Loewen, Charlie J. G.; Vinebrooke, Rolf D.

    2018-03-01

    Cumulative impacts of multiple stressors on freshwater biodiversity and ecosystem function likely increase with elevation, thereby possibly placing alpine communities at greatest risk. Here, consideration of species traits enables stressor effects on taxonomic composition to be translated into potential functional impacts. We analyzed data for 47 taxa across 137 mountain lakes and ponds spanning large latitudinal (491 km) and elevational (1,399 m) gradients in western Canada, to assess regional and local factors of the taxonomic composition and functional structure of zooplankton communities. Multivariate community analyses revealed that small body size, clonal reproduction via parthenogenesis, and lack of pigmentation were species traits associated with both introduced non-native sportfish and also environmental conditions reflecting a warmer and drier climate—namely higher water temperatures, shallower water depths, and more chemically concentrated water. Thus, historical introductions of sportfish appear to have potentially induced greater tolerance in zooplankton communities of future climatic warming, especially in previously fishless alpine lakes. Although alpine lake communities occupied a relatively small functional space (i.e., low functional diversity), they were contained within the broader regional functional structure. Therefore, our findings point to the importance of dispersal by lower montane species to the future functional stability of alpine communities.

  7. Spatial and seasonal changes in optical properties of autochthonous and allochthonous chromophoric dissolved organic matter in a stratified mountain lake.

    Science.gov (United States)

    Bracchini, Luca; Dattilo, Arduino Massimo; Hull, Vincent; Loiselle, Steven Arthur; Nannicini, Luciano; Picchi, Maria Pia; Ricci, Maso; Santinelli, Chiara; Seritti, Alfredo; Tognazzi, Antonio; Rossi, Claudio

    2010-03-01

    In this study, we present results on seasonal and spatial changes in CDOM absorption and fluorescence (fCDOM) in a deep mountain lake (Salto Lake, Italy). A novel approach was used to describe the shape of CDOM absorption between 250-700 nm (distribution of the spectral slope, S(lambda)) and a new fluorescence ratio is used to distinguish between humic and amino acid-like components. Solar ultraviolet irradiance, dissolved organic carbon (DOC), DOM fluorescence and absorption measurements were analysed and compared to other physicochemical parameters. We show that in the UV-exposed mixed layer: (i) fluorescence by autochthonous amino acid-like CDOM, (ii) values of S(lambda) across UV-C and UV-B wavebands increased during the summer months, whereas (i) average molar absorption coefficient and (ii) fluorescence by allochthonous humic CDOM decreased. In the unexposed deep layer of the water column (and in the entire water column in winter), humic-like CDOM presented high values of molar absorption coefficients and low values of S(lambda). UV attenuation coefficients correlated with both chlorophyll a concentrations and CDOM absorption. In agreement with changes in CDOM, minimal values in UV attenuation were found in summer. The S(lambda) curve was used as a signature of the mixture between photobleached and algal-derived CDOM with respect to the unexposed chromophoric dissolved compounds in this thermal stratified lake. Furthermore, S(lambda) curves were useful to distinguish between low and high molecular weight CDOM.

  8. Assessing Potential Algal Blooms in a Shallow Fluvial Lake by Combining Hydrodynamic Modelling and Remote-Sensed Images

    Directory of Open Access Journals (Sweden)

    Monica Pinardi

    2015-04-01

    Full Text Available Shallow fluvial lakes are dynamic ecosystems shaped by physical and biological factors and characterized by the coexistence of phytoplankton and macrophytes. Due to multiple interplaying factors, understanding the distribution of phytoplankton in fluvial lakes is a complex but fundamental issue, in the context of increasing eutrophication, climate change, and multiple water uses. We analyze the distribution of phytoplankton by combining remotely sensed maps of chlorophyll-a with a hydrodynamic model in a dammed fluvial lake (Mantua Superior Lake, Northern Italy. The numerical simulation of different conditions shows that the main hydrodynamic effects which influence algal distribution are related to the combined effect of advection due to wind forces and local currents, as well as to the presence of large gyres which induce recirculation and stagnation regions, favoring phytoplankton accumulation. Therefore, the general characters of the phytoplankton horizontal patchiness can be inferred from the results of the hydrodynamic model. Conversely, hyperspectral remote-sensing products can be used to validate this model, as they provide chlorophyll-a distribution maps. The integration of ecological, hydraulic, and remote-sensing techniques may therefore help the monitoring and protection of inland water quality, with important improvements in management actions by policy makers.

  9. Remote Sensing and Shallow Geophysical Investigations on Moghra Lake in Northeastern Qattarra Depression, Western Desert, Egypt

    Science.gov (United States)

    Khan, S. D.; Fathy, M. S.; Azeem, M. A.

    2012-12-01

    The Western Desert of Egypt encompasses two thirds of the land area of Egypt and constitutes one of the driest regions of the Sahara. This desert has seven depressions; Siwa, Qattara, Fayium, Bahariya, Farafra, Dakhla and Kharga. These depressions may be the manifestation of old drainage basins with extensive erosion and possibly some tectonic activity. Several oases with freshwater can be found in these depressions. Geological and geophysical investigations in Qattara Depression indicate several buried fluvial channels with flow direction from highlands in southeast to northwest. Moghra Lake at the northeastern tip of Qatarra basin may be a small remnant of a larger paleo-lake including the mouth of a paleo-river. This study probed this area for presence of buried channels that may have fed the larger Moghra paleo-lake. We have used ALOS - PALSAR radar remote sensing data to identify the surface features in this region, such as channels, channel fills, and fractures. In addition, dual polarization PALSAR data (HV, HH) allowed analysis of the near surface geology and assisted in delineating areas of interest for GPR surveys. GPR data along 2D profiles were acquired using the GSSI SIR-3000 system with a 400 MHz antenna that provided images to approximately three meters in depth. All the GPS data were processed using RADAN 6.6 software. A conventional processing flow was used for data processing: The positional correction tool removed the air wave. A range-gain balanced the amplitudes and a final band-pass (50 kHz to 500 kHz) filter was applied to the data. Deconvolution was also applied for highlighting the finer details. In addition, spatial filters were used to attenuate continuous vertical noise. The migrated sections of GPR identified a major paleochannel distributary with two minor channels at the margins. The bedrock of the studied area consists of the Lower Miocene Moghra Formation (sandstone and shale intercalations). The area around the present lake is

  10. Inherent optical properties and remote sensing reflectance of Pomeranian lakes (Poland

    Directory of Open Access Journals (Sweden)

    Dariusz Ficek

    2012-11-01

    Full Text Available This paper describes the results of comprehensive empirical studies of theinherent optical properties (IOPs, the remote sensing reflectance Rrs(λ andthe contents of the principal optically active components (OAC i.e. coloureddissolved organic matter (CDOM, suspended particulate matter (SPM andchlorophyll a, in the waters of 15 lakes in Polish Pomerania in 2007-2010.It presents numerous spectra of the total absorption a(λ andscattering b(λ ≈ bp(λ of light in the visibleband (400-700 nm for surface waters, and separately, spectra of absorptionby CDOM aCDOM(λ and spectra of the mass-specificcoefficients of absorption ap*(SPM(λ and scatteringbp*(SPM(λ by SPM. The properties of these lake waters are highly diverse, but all of them can beclassified as Case 2 waters (according to the optical classification by Morel& Prieur 1977 and they all have a relatively high OAC content. The lakeswere conventionally divided into three types: Type I lakes have the lowestOAC concentrations (chlorophyll concentration Ca = (8.76 ± 7.4 mg m-3 and CDOM absorption coefficientsaCDOM(440 = (0.57 ± 0.22 m-1 (i.e. mean and standarddeviation, and optical properties (including spectra of Rrs(λresembling those of Baltic waters. Type II waters have exceptionally highcontents of CDOM (aCDOM(440 = (15.37 ± 1.54 m-1,and hence appear brown in daylight and have very low reflectancesRrs(λ (of the order of 0.001 sr-1. Type III waters arehighly eutrophic and contain large amounts of suspended matter, includingphytoplankton ((CSPM = (47.0 ± 39.4 g m-3,Ca = (86.6 ± 61.5 mg m-3; aCDOM(440 = (2.77 ± 0.86 m-1. Hence the reflectances Rrs(λof these type of waters are on average one order of magnitude higher thanthose of the other natural waters, reaching maximum values of 0.03 sr-1in λ bands 560-580 nm and 690-720 nm (see Ficek et al. 2011. Thearticle provides a number of empirical formulas approximating therelationships between the properties of these lake waters.

  11. Remote Sensing of Hydrological Changes in Tian-e-Zhou Oxbow Lake, an Ungauged Area of the Yangtze River Basin

    Directory of Open Access Journals (Sweden)

    Chao Yang

    2017-12-01

    Full Text Available The hydrological pattern changes have a great influence on the wetland environment. However, some important wetland areas often lack historical observations due to economic and physical conditions. The Tian-e-Zhou oxbow lake wetland is an important habitat for two endangered species and also has very little historical hydrological data. Remote sensing images can be used to explore the historical water area fluctuation of lakes. In addition, remote sensing can also be used to obtain historical water levels based on the water boundary elevation integrated with a topographic data (WBET method or the level-surface area relationship curve (LRC method. In order to minimize the uncertainty of the derived results, both methods were introduced in the extraction of the water level of Tian-e-Zhou during 1992–2015. The results reveal that the hydrological regime of the oxbow lake has experienced a significant change after the Shatanzi Levee construction in 1998. With the impact of the levee, the mean annual water surface area of the lake was reduced by 5.8 km2 during the flood season, but, during the non-flood season, it was increased by 1.35 km2. For the same period, the water level of the lake during the flood season also showed a 1.47 m (WBET method or 3.21 m (LRC method decrease. The mean annual water level increased by 1.12 m (WBET method or 0.75 m (LRC method. Both results had a good accuracy with RMSE (root-mean-square errors of less than 0.4 m. Furthermore, the water level differences between the Yangtze River channel and the oxbow lake increased by at least 0.5 m. It is found that the hydrological pattern of the oxbow lake changed significantly after the levee construction, which could bring some disadvantages to the habitats of the two endangered species.

  12. APPLICATION OF REMOTE SENSING DATA FOR THE ASSESSMENT OF THE UJUK MOUNTAIN BOREAL FORESTS (THE TYVA REPUBLIC, RUSSIA

    Directory of Open Access Journals (Sweden)

    Khulermaa B. Kuular

    2016-01-01

    Full Text Available This paper discusses some issues related to assessment and monitoring of forests insouthern Siberia. This study aims to evaluate the response of southern boreal forests to climate warming at local scale. Estimating the impacts of climate change on mountain boreal forests requires a more complete accounting of tree growth/climate interaction. We used both remote sensing and field data. Field measurements were made from the upper to lower timberline of dark deciduous forest in 2005 and 2012. The remote sensing datasets were generated from LANDSAT scenes of different dates (19.08.1988, 25.06.1992 and 18.08.2011. For estimation of forests changes, we used values of NDVI (Normalized Difference Vegetation Index and NBR (Normalized Burn Ratio.

  13. Identification of the glaciers and mountain naturally dammed lakes in the Pskem, the Kashkadarya and the Surhandarya River basins, Uzbekistan, using ALOS satellite data

    Directory of Open Access Journals (Sweden)

    Eleonora Semakova

    2016-05-01

    Full Text Available The glacierized area of Uzbekistan is represented in three river basins – the Pskem, the Kashkadarya and the Surhandarya. This study considers the present state of the glaciers and high-mountain lakes distribution in this area based on the analysis and validation of advanced land observing satellite (ALOS/advanced visible and near infrared radiometer type 2 (AVNIR-2 satellite data. Between the 1960s and the 2010s, the glacierized area decreased by 23% in the Pskem River basin (including the Maydantal, by 49% in the Kashkadarya and by 40% in the Surhandarya (including the Sangardak and the Tupalang River basins. The retreat fairly slowed in the 1980s–2010s. There are 75 glacial lakes and 35 rock-dammed lakes (including landslide-dammed ones in the Pskem River basin, 45% of all the lakes covering the area less than 0.002 km2; 13 glacial lakes and 4 rock-dammed lakes in the Kashkadarya and 34 glacial lakes and 16 rock-dammed lakes in the Surhandarya River basins. The landslide rock-dammed Ikhnach Upper Lake lost 0.04 km2 in size from 1 August 2010 to 30 August 2010 because of the seepage through the rock dam and 0.10 km2 from 1 August to 18 October 2013.

  14. Development of a Three Dimensional Wireless Sensor Network for Terrain-Climate Research in Remote Mountainous Environments

    Science.gov (United States)

    Kavanagh, K.; Davis, A.; Gessler, P.; Hess, H.; Holden, Z.; Link, T. E.; Newingham, B. A.; Smith, A. M.; Robinson, P.

    2011-12-01

    Developing sensor networks that are robust enough to perform in the world's remote regions is critical since these regions serve as important benchmarks compared to human-dominated areas. Paradoxically, the factors that make these remote, natural sites challenging for sensor networking are often what make them indispensable for climate change research. We aim to overcome these challenges by developing a three-dimensional sensor network arrayed across a topoclimatic gradient (1100-1800 meters) in a wilderness area in central Idaho. Development of this sensor array builds upon advances in sensing, networking, and power supply technologies coupled with experiences of the multidisciplinary investigators in conducting research in remote mountainous locations. The proposed gradient monitoring network will provide near real-time data from a three-dimensional (3-D) array of sensors measuring biophysical parameters used in ecosystem process models. The network will monitor atmospheric carbon dioxide concentration, humidity, air and soil temperature, soil water content, precipitation, incoming and outgoing shortwave and longwave radiation, snow depth, wind speed and direction, tree stem growth and leaf wetness at time intervals ranging from seconds to days. The long-term goal of this project is to realize a transformative integration of smart sensor networks adaptively communicating data in real-time to ultimately achieve a 3-D visualization of ecosystem processes within remote mountainous regions. Process models will be the interface between the visualization platforms and the sensor network. This will allow us to better predict how non-human dominated terrestrial and aquatic ecosystems function and respond to climate dynamics. Access to the data will be ensured as part of the Northwest Knowledge Network being developed at the University of Idaho, through ongoing Idaho NSF-funded cyber infrastructure initiatives, and existing data management systems funded by NSF, such as

  15. Assimilation of remote sensing observations into a sediment transport model of China's largest freshwater lake: spatial and temporal effects.

    Science.gov (United States)

    Zhang, Peng; Chen, Xiaoling; Lu, Jianzhong; Zhang, Wei

    2015-12-01

    Numerical models are important tools that are used in studies of sediment dynamics in inland and coastal waters, and these models can now benefit from the use of integrated remote sensing observations. This study explores a scheme for assimilating remotely sensed suspended sediment (from charge-coupled device (CCD) images obtained from the Huanjing (HJ) satellite) into a two-dimensional sediment transport model of Poyang Lake, the largest freshwater lake in China. Optimal interpolation is used as the assimilation method, and model predictions are obtained by combining four remote sensing images. The parameters for optimal interpolation are determined through a series of assimilation experiments evaluating the sediment predictions based on field measurements. The model with assimilation of remotely sensed sediment reduces the root-mean-square error of the predicted sediment concentrations by 39.4% relative to the model without assimilation, demonstrating the effectiveness of the assimilation scheme. The spatial effect of assimilation is explored by comparing model predictions with remotely sensed sediment, revealing that the model with assimilation generates reasonable spatial distribution patterns of suspended sediment. The temporal effect of assimilation on the model's predictive capabilities varies spatially, with an average temporal effect of approximately 10.8 days. The current velocities which dominate the rate and direction of sediment transport most likely result in spatial differences in the temporal effect of assimilation on model predictions.

  16. Hydroclimatology of Lake Victoria region using hydrologic model and satellite remote sensing data

    Directory of Open Access Journals (Sweden)

    S. I. Khan

    2011-01-01

    Full Text Available Study of hydro-climatology at a range of temporal scales is important in understanding and ultimately mitigating the potential severe impacts of hydrological extreme events such as floods and droughts. Using daily in-situ data over the last two decades combined with the recently available multiple-years satellite remote sensing data, we analyzed and simulated, with a distributed hydrologic model, the hydro-climatology in Nzoia, one of the major contributing sub-basins of Lake Victoria in the East African highlands. The basin, with a semi arid climate, has no sustained base flow contribution to Lake Victoria. The short spell of high discharge showed that rain is the prime cause of floods in the basin. There is only a marginal increase in annual mean discharge over the last 21 years. The 2-, 5- and 10- year peak discharges, for the entire study period showed that more years since the mid 1990's have had high peak discharges despite having relatively less annual rain. The study also presents the hydrologic model calibration and validation results over the Nzoia basin. The spatiotemporal variability of the water cycle components were quantified using a hydrologic model, with in-situ and multi-satellite remote sensing datasets. The model is calibrated using daily observed discharge data for the period between 1985 and 1999, for which model performance is estimated with a Nash Sutcliffe Efficiency (NSCE of 0.87 and 0.23% bias. The model validation showed an error metrics with NSCE of 0.65 and 1.04% bias. Moreover, the hydrologic capability of satellite precipitation (TRMM-3B42 V6 is evaluated. In terms of reconstruction of the water cycle components the spatial distribution and time series of modeling results for precipitation and runoff showed considerable agreement with the monthly model runoff estimates and gauge observations. Runoff values responded to precipitation events that occurred across the catchment during the wet season from March to

  17. Combining Hydrological Modeling and Remote Sensing Observations to Enable Data-Driven Decision Making for Devils Lake Flood Mitigation in a Changing Climate

    Science.gov (United States)

    Zhang, Xiaodong; Kirilenko, Andrei; Lim, Howe; Teng, Williams

    2010-01-01

    This slide presentation reviews work to combine the hydrological models and remote sensing observations to monitor Devils Lake in North Dakota, to assist in flood damage mitigation. This reports on the use of a distributed rainfall-runoff model, HEC-HMS, to simulate the hydro-dynamics of the lake watershed, and used NASA's remote sensing data, including the TRMM Multi-Satellite Precipitation Analysis (TMPA) and AIRS surface air temperature, to drive the model.

  18. Climatic Characteristics of the Subtropical Mountainous Cloud Forest at the Yuanyang Lake Long-Term Ecological Research Site, Taiwan

    Directory of Open Access Journals (Sweden)

    I-Ling Lai

    2006-12-01

    Full Text Available To better understand the climatic characteristics in a subtropical mountainous cloud forest at the Yuanyang Lake long-term ecological research site, weather data collected from January 1994 to December 2004 were analyzed in the present study. The obvious seasonal changes in climatic factors were observed at this site. The annual mean air temperature was 12.7°C. The lowest temperature was recorded in February (monthly mean 5.9°C, and the highest one was taken in July (monthly mean 18.1°C. Winter featured light rain with a prolonged occurrence of fog, resulting in a large reduction of radiation. In summer, fog occurred once in the early morning and the other time from afternoon to evening. The latter one was associated with the wind direction changes and usually accompanied with short moderate to heavy convective rain. Consequently the photosynthetic photon flux density (PPFD was high in the morning but reduced drastically in the afternoon. Typhoons occurred in the summer had contributed to 37% of the annual rainfall, usually resulting in torrential rain events and sharp increases in the water level of this lake. As a matter of fact, perhumid environment of this site was attributed to abundant rainfall (mean annual precipitation 3396 mm and high frequency (up to 40% of foggy time. Such conditions would reduce the intensity of solar radiation and PPFD. The average annual solar radiation at the site was 2475 MJ m-2, and annual PPFD was 5713 mol m-2. The average degree of reduction of PPFD under foggy condition was up to 88%. Such climatic characteristics are suggested to constrain the growth of plants and play an important role in competition among plant species in this cloud forest. It is considered that the distinct seasonal fluctuation in environmental factors, perhumid and dim light conditions are the most distinguished characteristics of this subtropical mountainous cloud forest ecosystem.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  1. 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

    Energy Technology Data Exchange (ETDEWEB)

    Jarque, Sergio; Gallego, Eva [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain); Bartrons, Mireia; Catalan, Jordi [Center for Advanced Studies of Blanes (CEAB-CSIC), Acces Cala St. Francesc 14, 17300-Blanes, Catalonia (Spain); Grimalt, Joan O. [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain); Pina, Benjamin, E-mail: bpcbmc@cid.csic.e [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034-Barcelona, Catalonia (Spain)

    2010-05-15

    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 deg. C and +6.2 deg. 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. - Altitudinal gradients of hepatic Cyp1A gene expression in mountain trout correlate with geographic and individual organohalogen distribution.

  2. Catchment biogeochemistry modifies long-term effects of acidic deposition on chemistry of mountain lakes

    Czech Academy of Sciences Publication Activity Database

    Kopáček, Jiří; Bičárová, S.; Hejzlar, Josef; Hynštová, M.; Kaňa, Jiří; Mitošinková, M.; Porcal, Petr; Stuchlík, E.; Turek, Jan

    2015-01-01

    Roč. 125, č. 3 (2015), s. 315-335 ISSN 0168-2563 R&D Projects: GA ČR(CZ) GA14-09231S Institutional support: RVO:60077344 Keywords : Alpine lakes * dissolved organic carbon * nitrogen * phosphorus * sulphate * chloride Subject RIV: DJ - Water Pollution ; Quality Impact factor: 3.407, year: 2015

  3. Pollen and macroscopic analyses of sediments from two lakes in the High Tatra mountains, Slovakia

    Czech Academy of Sciences Publication Activity Database

    Rybníčková, Eliška; Rybníček, Kamil

    2006-01-01

    Roč. 15, - (2006), s. 345-356 ISSN 0939-6314 R&D Projects: GA ČR(CZ) GA206/96/0531; GA ČR GA206/02/0568 Institutional research plan: CEZ:AV0Z60050516 Keywords : Pollen analyses * macroscopic analyses * high mointain lakes Subject RIV: EF - Botanics Impact factor: 0.649, year: 2006

  4. Bacteria and pelagic food webs in Pristine alpine lakes (Retezat Mountains, Romania)

    Czech Academy of Sciences Publication Activity Database

    Straškrábová, Viera; Cogalniceanu, D.; Nedoma, Jiří; Parpala, L.; Postolache, C.; Tudorancea, C.; Vadineanu, A.; Valcu, C. M.; Zinevici, V.

    2006-01-01

    Roč. 3, - (2006), s. 1-10 ISSN 1841-7051 Grant - others:EC(XE) EVK1-CT-1999-00032; EC(XE) GOCE-CT-2003-505298 Institutional research plan: CEZ:AV0Z60170517 Keywords : alpine lakes * pelagic bacteria * chlorophyll * zooplankton Subject RIV: EH - Ecology, Behaviour

  5. Landslide hazard assessment along a mountain highway in the Indian Himalayan Region (IHR) using remote sensing and computational models

    Science.gov (United States)

    Krishna, Akhouri P.; Kumar, Santosh

    2013-10-01

    Landslide hazard assessments using computational models, such as artificial neural network (ANN) and frequency ratio (FR), were carried out covering one of the important mountain highways in the Central Himalaya of Indian Himalayan Region (IHR). Landslide influencing factors were either calculated or extracted from spatial databases including recent remote sensing data of LANDSAT TM, CARTOSAT digital elevation model (DEM) and Tropical Rainfall Measuring Mission (TRMM) satellite for rainfall data. ANN was implemented using the multi-layered feed forward architecture with different input, output and hidden layers. This model based on back propagation algorithm derived weights for all possible parameters of landslides and causative factors considered. The training sites for landslide prone and non-prone areas were identified and verified through details gathered from remote sensing and other sources. Frequency Ratio (FR) models are based on observed relationships between the distribution of landslides and each landslide related factor. FR model implementation proved useful for assessing the spatial relationships between landslide locations and factors contributing to its occurrence. Above computational models generated respective susceptibility maps of landslide hazard for the study area. This further allowed the simulation of landslide hazard maps on a medium scale using GIS platform and remote sensing data. Upon validation and accuracy checks, it was observed that both models produced good results with FR having some edge over ANN based mapping. Such statistical and functional models led to better understanding of relationships between the landslides and preparatory factors as well as ensuring lesser levels of subjectivity compared to qualitative approaches.

  6. On a possibility to use the remote sensing techniques for glaciological analysis in mountain regions of Uzbekistan

    Directory of Open Access Journals (Sweden)

    E. R. Semakova

    2017-01-01

    Full Text Available The ALOS/AVNIR-2 satellite data (2007–2010 allowed estimating areas of glaciers, change in the areas for 50 years, and the number and areas of new naturally-dammed lakes in the mountain regions of Uzbekistan. Boundaries of these gla‑ ciers together with the ALOS/PALSAR data (2010 were used as the basis to determine position of the firn line. It was revealed that since 1980s elevation range of the line gradually decreased. The relationship between average elevation of the firn line and the upper limit of the juniper tree occurrence as well as changing of this relation since 1980s are consid‑ ered. The revealed lakes served as the basis for verification of probabilistic model of the moraine-dammed lake forma‑ tions due to the glacier recessions in the basins under consideration. It was shown that the GIS-techniques based on the use of this model together with data on glaciation and the relief digital model may significantly simplify searching of new lakes. Application of a system of the mudflow movement modeling makes possible to estimate a risk level in a case of a lake bursting. Current information about changing elevations of the glacier surfaces was obtained duet to the radar inter‑ ferometry and the altimeter data. The digital model of the river Pskem upper course (the DEM had been built using the satellite TerraSAR‑X/TanDEM‑X data (2011–2012. All datasets of the elevations were checked for horizontal shifts of the relief digital models relative to the ICESat profiles (2003–2008. Evaluation of accuracy and morphological analysis of all the relief models for the investigated region were also made. DEMs differencing, the difference between ICESat measure‑ ments and DEM, nearby ICESat footprints within one track and between the tracks were carried out to assess the change in elevations of the glacier surfaces. Average rate of the surface lowering of an individual glacier with the maximal number of footprints (7 in the track

  7. Predicting aquatic macrophyte occurrence in soft-water oligotrophic lakes (Pyrenees mountain range

    Directory of Open Access Journals (Sweden)

    Cristina Pulido

    2014-08-01

    Full Text Available Distribution of aquatic macrophytes in lakes is related to geographical, morphological, catchment and water chemistry variables as well as human impacts, which modify the original environment. Here, we aim at building statistical models to establish the ecological niches of 11 aquatic macrophytes (10 different phanerogams and the genus Nitella from oligotrophic soft-water lakes and infer their ecological requirements and environmental constraints at the southernmost limit of their distribution. Macrophyte occurrence and environmental variables were obtained from 86 non-exploited oligotrophic soft-water lakes from the Pyrenees (Southern Europe; 42º50´N, 1º00´E; macrophytes inhabited 55 of these lakes. Optimum ranges and macrophyte occurrence were predicted in relation to 18 geographical, morphological, catchment and water chemistry variables using univariate and multivariate logistic models. Lakes at low altitude, in vegetated catchments and with low water concentration of NO3- and SO4-2, were the most suitable to host macrophytes. In general, individual species of aquatic macrophytes showed clear patterns of segregation along conductivity and pH gradients, although the specific combination of variables selected in the best models explaining their occurrence differed among species.  Based on the species response to pH and conductivity, we found Isoetes lacustris have its optimum in waters with low conductivity and pH (i.e. negative monotonic response. In contrast, Callitriche palustris, Ranunculus aquatilis, Subularia aquatica, Nitella spp., and Myriophyllum alterniflorum showed an optimum at intermediate values (i.e. unimodal response, whereas Potamogeton berchtoldii, Potamogeton alpinus, and Ranunculus trichophyllus as species had their optimum at relatively high water pH and conductivity (i.e. positive monotonic response. This pattern has been observed in other regions for the same species, although with different optima and tolerance

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

    Science.gov (United States)

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

    2010-09-01

    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 microm) 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.

  9. Quick Release of Internal Water Storage in a Glacier Leads to Underestimation of the Hazard Potential of Glacial Lake Outburst Floods From Lake Merzbacher in Central Tian Shan Mountains

    Science.gov (United States)

    Shangguan, Donghui; Ding, Yongjian; Liu, Shiyin; Xie, Zunyi; Pieczonka, Tino; Xu, Junli; Moldobekov, Bolot

    2017-10-01

    Glacial meltwater and ice calving contribute to the flood volume of glacial lakes such as Lake Merzbacher in the Tian Shan Mountains of central Asia. In this study, we simulated the lake's volume by constructing an empirical relationship between the area of Lake Merzbacher, determined from satellite images, and the lake's water storage, derived from digital elevation models. Results showed that the lake water supply rate before Glacial Lake Outburst Floods (GLOFs) generally agreed well with those during the GLOFs from 2009 to 2012 but not in 2008 and 2015. Furthermore, we found that the combination of glacial meltwater and ice calving is not enough to fully explain the supply rate during GLOFs in 1996 and 1999, suggesting other factors affect the supply rate during GLOFs as well. To examine this further, we compared the water supply rate before and during GLOF events in 1999 and 2008. We inferred that quickly released short-term and intermediate-term water storage by glaciers have likely contributed to both flood events in those years. This study highlights the need to improve our understanding of the supply component of outburst floods, such as irregularly released stored water may lead to GLOF events with generally three different types: case I (singular event-triggered englacial water release), case II (glacier melt due to temperature changes), and case III (englacial water release mixed with glacier melt).

  10. Forest blowdown and lake acidification

    International Nuclear Information System (INIS)

    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 -0.67 and -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

  11. Remote sensing and geophysical investigations of Moghra Lake in the Qattara Depression, Western Desert, Egypt

    Science.gov (United States)

    Khan, Shuhab D.; Fathy, Mohamed S.; Abdelazeem, Maha

    2014-02-01

    The Western Desert covers two-thirds of the land area of Egypt and occupies one of the driest regions of the Sahara. Seven depressions within the desert - Siwa, Qattara, Fayum, Bahariya, Farafra, Dakhla, and Kharga - may represent parts of old drainage systems with deflation, extensive erosion, and possibly, some tectonic activity. Oases with freshwater exist in these depressions. Geological and geophysical investigations in the Qattara Depression indicate the presence of buried fluvial channels with southeast to northwest flow directions from the highland areas. The origin of these fluvial systems, as well as the origin of the depressions themselves, is still unresolved, and many ideas have been suggested. Moghra Lake at the northeastern tip of the Qattara basin may be a remnant of a larger paleolake, including the mouth of a paleo-river. We present here the results of our recent work in this area using ALOS PALSAR radar remote sensing data, which indicated the presence of buried channels that may have fed the larger Moghra paleolake. Ground penetrating radar (GPR) data along 2D profiles were acquired; the migrated GPR sections identified a major paleochannel with numerous minor channels at its margins. GPR interpretations are verified by field observations, trenching, and stratigraphic information from outcrop data. Potential field analyses identify possible aquifers that are controlled by regional structures. Density contrasts within the sedimentary units, physical boundaries of uplifted basement blocks and depths to causative sources were also identified. This work contributes to the reconstruction of paleodrainage of this region and helps in understanding processes involved in the formation of the Qattara Depression.

  12. Analysis of the Tonle Sap Flood Pulse Based on Remote Sensing: how much does Tonle Sap Lake Affect the Mekong River Flood?

    Science.gov (United States)

    Qu, W.; Hu, N.; Fu, J.; Lu, J.; Lu, H.; Lei, T.; Pang, Z.; Li, X.; Li, L.

    2018-04-01

    The economic value of the Tonle Sap Lake Floodplain to Cambodia is among the highest provided to a nation by a single ecosystem around the world. The flow of Mekong River is the primary factor affecting the Tonle Sap Lake Floodplain. The Tonle Sap Lake also plays a very important role in regulating the downstream flood of Mekong River. Hence, it is necessary to understand its temporal changes of lake surface and water storage and to analyse its relation with the flood processes of Mekong River. Monthly lake surface and water storage from July 2013 to May 2014 were first monitored based on remote sensing data. The relationship between water surface and accumulative water storage change was then established. In combination with hydrological modelling results of Mekong River Basin, the relation between the lake's water storage and the runoff of Mekong River was analysed. It is found that the water storage has a sharp increase from September to December and, after reaching its maximum in December, water storage quickly decreases with a 38.8 billion m3 of drop in only half month time from December to January, while it keeps rather stable at a lower level in other months. There is a two months' time lag between the maximum lake water storage and the Mekong River peak flood, which shows the lake's huge flood regulation role to downstream Mekong River. It shows that this remote sensing approach is feasible and reliable in quantitative monitoring of data scarce lakes.

  13. Fusion of hyperspectral remote sensing data for near real-time monitoring of microcystin distribution in Lake Erie

    Science.gov (United States)

    Vannah, Benjamin; Chang, Ni-Bin

    2013-09-01

    Urban growth and agricultural production have caused an influx of nutrients into Lake Erie, leading to eutrophic zones. These conditions result in the formation of algal blooms, some of which are toxic due to the presence of Microcystis (a cyanobacteria), which produces the hepatotoxin microcystin. Microcystis has a unique advantage over its competition as a result of the invasive zebra mussel population that filters algae out of the water column except for the toxic Microcystis. The toxin threatens human health and the ecosystem, and it is a concern for water treatment plants using the lake water as a tap water source. This presentation demonstrates the prototype of a near real-time early warning system using Integrated Data Fusion techniques with the aid of both hyperspectral remote sensing data to determine spatiotemporal microcystin concentrations. The temporal resolution of MODIS is fused with the higher spatial and spectral resolution of MERIS to create synthetic images on a daily basis. As a demonstration, the spatiotemporal distributions of microcystin within western Lake Erie are reconstructed using the band data from the fused products and applied machine-learning techniques. Analysis of the results through statistical indices confirmed that the this type of algorithm has better potential to accurately estimating microcystin concentrations in the lake, which is better than current two band models and other computational intelligence models.

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

    Science.gov (United States)

    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.

  15. Advances in the application of remote sensing and GIS for surveying mountainous land

    NARCIS (Netherlands)

    Mulders, M.A.

    2001-01-01

    Satellite remote sensing has been practised since 1972, starting with broad channels and moderate ground resolution (Landsat MSS). In the 1980s, Landsat TM and SPOT provided for improved spatial and spectral resolutions. Many satellite images were produced in these two decades, offering a synoptic

  16. Estimating above-ground biomass on mountain meadows and pastures through remote sensing

    Science.gov (United States)

    Barrachina, M.; Cristóbal, J.; Tulla, A. F.

    2015-06-01

    Extensive stock-breeding systems developed in mountain areas like the Pyrenees are crucial for local farming economies and depend largely on above-ground biomass (AGB) in the form of grass produced on meadows and pastureland. In this study, a multiple linear regression analysis technique based on in-situ biomass collection and vegetation and wetness indices derived from Landsat-5 TM data is successfully applied in a mountainous Pyrenees area to model AGB. Temporal thoroughness of the data is ensured by using a large series of images. Results of on-site AGB collection show the importance for AGB models to capture the high interannual and intraseasonal variability that results from both meteorological conditions and farming practices. AGB models yield best results at midsummer and end of summer before mowing operations by farmers, with a mean R2, RMSE and PE for 2008 and 2009 midsummer of 0.76, 95 g m-2 and 27%, respectively; and with a mean R2, RMSE and PE for 2008 and 2009 end of summer of 0.74, 128 g m-2 and 36%, respectively. Although vegetation indices are a priori more related with biomass production, wetness indices play an important role in modeling AGB, being statistically selected more frequently (more than 50%) than other traditional vegetation indexes (around 27%) such as NDVI. This suggests that middle infrared bands are crucial descriptors of AGB. The methodology applied in this work compares favorably with other works in the literature, yielding better results than those works in mountain areas, owing to the ability of the proposed methodology to capture natural and anthropogenic variations in AGB which are the key to increasing AGB modeling accuracy.

  17. Remote sensing of euphotic depth in shallow tropical inland waters of Lake Naivasha using MERIS data

    CSIR Research Space (South Africa)

    Majozi, NP

    2014-05-01

    Full Text Available radiometric and limnological data collection was undertaken at Lake Naivasha. Atmospheric correction was done on the MERIS images using MERIS Neural Network algorithms, Case 2 Waters (C2R) and Eutrophic Lakes processors and the bright pixel atmospheric...

  18. Capturing variations in inundation with satellite remote sensing in a morphologically complex, large lake

    Science.gov (United States)

    Wu, Guiping; Liu, Yuanbo

    2015-04-01

    Poyang Lake is the largest freshwater lake in China, with high morphological complexity from south to north. In recent years, the lake has experienced expansion and shrinkage processes over both short- and long-term scales, resulting in significant hydrological, ecological and economic problems. Exactly how and how rapidly the processes of spatial change have occurred in the lake during the expansion and shrinkage periods is unknown. Such knowledge is of great importance for policymakers as it may help with flood/drought prevention, land use planning and lake ecological conservation. In this study, we investigated the spatial-temporal distribution and changing processes of inundation in Poyang Lake based on Moderate Resolution Imaging Spectroradiometer (MODIS) Level-1B data from 2000 to 2011. A defined water variation rate (WVR) and inundation frequency (IF) indicator revealed the water surface submersion and exposure processes of lake expansion and shrinkage in different zones which were divided according to the lake's hydrological and topographic features. Regional differences and significant seasonality variability were found in the annual and monthly mean IF. The monthly mean IF increased slowly from north to south during January-August but decreased quickly from south to north during September-December. During the lake expansion period, the lake-type water body zone (Zone II) had the fastest expansion rate, with a mean monthly WVR value of 34.47% in February-March, and was followed by the channel-type water body zone (Zone I) in March-May (22.47%). However, during the lake shrinkage period, rapid shrinkage first appeared around the alluvial delta zones in August-October. The sequence of lake surface shrinkage from August to December is exactly opposite to that of lake expansion from February to July. These complex inundation characteristics and changing process were driven by the high temporal variability of the river flows, the morphological diversity of the

  19. Water level monitoring using radar remote sensing data: Application to Lake Kivu, central Africa

    Science.gov (United States)

    Munyaneza, Omar; Wali, Umaru G.; Uhlenbrook, Stefan; Maskey, Shreedhar; Mlotha, McArd J.

    Satellite radar altimetry measures the time required for a pulse to travel from the satellite antenna to the earth’s surface and back to the satellite receiver. Altimetry on inland lakes generally shows some deviation from in situ level measurements. The deviation is attributed to the geographically varying corrections applied to account for atmospheric effects on radar waves. This study was focused on verification of altimetry data for Lake Kivu (2400 km 2), a large inland lake between Rwanda and the Democratic Republic of Congo (DRC) and estimating the lake water levels using bathymetric data combined with satellite images. Altimetry data obtained from ENVISAT and ERS-2 satellite missions were compared with water level data from gauging stations for Lake Kivu. Gauge data for Lake Kivu were collected from the stations ELECTROGAZ and Rusizi. ENVISAT and ERS-2 data sets for Lake Kivu are in good agreement with gauge data having R2 of 0.86 and 0.77, respectively. A combination of the two data sets improved the coefficient of determination to 95% due to the improved temporal resolution of the data sets. The calculated standard deviation for Lake Kivu water levels was 0.642 m and 0.701 m, for ENVISAT and ERS-2 measurements, respectively. The elevation-surface area characteristics derived from bathymetric data in combination with satellite images were used to estimate the lake level gauge. Consequently, the water level of Lake Kivu could be estimated with an RMSE of 0.294 m and an accuracy of ±0.58 m. In situations where gauges become malfunctioning or inaccessible due to damage or extreme meteorological events, the method can be used to ensure data continuity.

  20. MOLAR. Measuring and modelling the dynamic response of remote mountain lake ecosystems to environmental change: A programme of Mountain Lake Research. MOLAR Project Manual. Draft of September 1996

    Energy Technology Data Exchange (ETDEWEB)

    Wathne, B M

    1996-09-01

    This report lays down the practical working methods of the MOLAR project. Requirements on preparatory work and methods for sampling in the field are given in detail. Also sample handling after field work, where to send the sample material for further analysis and how to treat the results are described. 97 refs., 10 figs., 14 tabs.

  1. Spatial and Temporal Variability of Dust Deposition in the San Juan Mountains, CO: A Network of Late Holocene Lake Sediment Records

    Science.gov (United States)

    Arcusa, S.; Routson, C.; McKay, N.

    2017-12-01

    Millions of stakeholders living in the arid southwestern US rely on snowmelt from the San Juan Mountains of Colorado. However, dust deposition on snow accelerates snowmelt, challenging water management. Dustiness in the southwestern US is primarily mediated by drought, which is projected to increase in frequency and severity. Over the past several millennia, multidecadal-length megadroughts are hypothesized to have enhanced regional dustiness. These past megadroughts were more frequent during the Roman (ca. 1-400 CE) and Medieval (ca. 800-1300 CE) time periods and were similar in duration and severity to those projected for the future. Developing an understanding of the temporal and spatial patterns of past dust deposition in the San Juan Mountains will help inform adaptation strategies for future droughts. A network of short sediment cores from six alpine lakes in the San Juan Mountains were collected in 2016 and 2017 to investigate the spatial patterns of dust deposition. The range in lake basin characteristics in the network, such as catchment size, helps to constrain the influence of secondary dust deposition. Grain size analysis and X-ray Fluorescence were combined with radiocarbon dating to trace the temporal patterns in dust flux over the Late Holocene (the last 2000 years). The End-member Modelling Algorithm (EMMA) was used to estimate the dust proportion in the lake sediment, distinguishing from locally derived catchment material. Comparisons to modern dust-on-snow samples were made to identify the dust size distribution. The results show that deposition trends were not uniform between the south-eastern and north-western San Juans, with increasing trends towards the present in the former, possibly reflecting a shift in dust sources associated with changes in wind speed and direction. Dust levels greater than long term averages were recorded during the Medieval and Roman periods. The network also showed the influence of lake basin parameters, such as the

  2. Ecological Sensitivity Evaluation of Tourist Region Based on Remote Sensing Image - Taking Chaohu Lake Area as a Case Study

    Science.gov (United States)

    Lin, Y.; Li, W. J.; Yu, J.; Wu, C. Z.

    2018-04-01

    Remote sensing technology is of significant advantages for monitoring and analysing ecological environment. By using of automatic extraction algorithm, various environmental resources information of tourist region can be obtained from remote sensing imagery. Combining with GIS spatial analysis and landscape pattern analysis, relevant environmental information can be quantitatively analysed and interpreted. In this study, taking the Chaohu Lake Basin as an example, Landsat-8 multi-spectral satellite image of October 2015 was applied. Integrated the automatic ELM (Extreme Learning Machine) classification results with the data of digital elevation model and slope information, human disturbance degree, land use degree, primary productivity, landscape evenness , vegetation coverage, DEM, slope and normalized water body index were used as the evaluation factors to construct the eco-sensitivity evaluation index based on AHP and overlay analysis. According to the value of eco-sensitivity evaluation index, by using of GIS technique of equal interval reclassification, the Chaohu Lake area was divided into four grades: very sensitive area, sensitive area, sub-sensitive areas and insensitive areas. The results of the eco-sensitivity analysis shows: the area of the very sensitive area was 4577.4378 km2, accounting for about 37.12 %, the sensitive area was 5130.0522 km2, accounting for about 37.12 %; the area of sub-sensitive area was 3729.9312 km2, accounting for 26.99 %; the area of insensitive area was 382.4399 km2, accounting for about 2.77 %. At the same time, it has been found that there were spatial differences in ecological sensitivity of the Chaohu Lake basin. The most sensitive areas were mainly located in the areas with high elevation and large terrain gradient. Insensitive areas were mainly distributed in slope of the slow platform area; the sensitive areas and the sub-sensitive areas were mainly agricultural land and woodland. Through the eco-sensitivity analysis of

  3. ECOLOGICAL SENSITIVITY EVALUATION OF TOURIST REGION BASED ON REMOTE SENSING IMAGE – TAKING CHAOHU LAKE AREA AS A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Y. Lin

    2018-04-01

    Full Text Available Remote sensing technology is of significant advantages for monitoring and analysing ecological environment. By using of automatic extraction algorithm, various environmental resources information of tourist region can be obtained from remote sensing imagery. Combining with GIS spatial analysis and landscape pattern analysis, relevant environmental information can be quantitatively analysed and interpreted. In this study, taking the Chaohu Lake Basin as an example, Landsat-8 multi-spectral satellite image of October 2015 was applied. Integrated the automatic ELM (Extreme Learning Machine classification results with the data of digital elevation model and slope information, human disturbance degree, land use degree, primary productivity, landscape evenness , vegetation coverage, DEM, slope and normalized water body index were used as the evaluation factors to construct the eco-sensitivity evaluation index based on AHP and overlay analysis. According to the value of eco-sensitivity evaluation index, by using of GIS technique of equal interval reclassification, the Chaohu Lake area was divided into four grades: very sensitive area, sensitive area, sub-sensitive areas and insensitive areas. The results of the eco-sensitivity analysis shows: the area of the very sensitive area was 4577.4378 km2, accounting for about 37.12 %, the sensitive area was 5130.0522 km2, accounting for about 37.12 %; the area of sub-sensitive area was 3729.9312 km2, accounting for 26.99 %; the area of insensitive area was 382.4399 km2, accounting for about 2.77 %. At the same time, it has been found that there were spatial differences in ecological sensitivity of the Chaohu Lake basin. The most sensitive areas were mainly located in the areas with high elevation and large terrain gradient. Insensitive areas were mainly distributed in slope of the slow platform area; the sensitive areas and the sub-sensitive areas were mainly agricultural land and woodland

  4. Remote estimation of colored dissolved organic matter and chlorophyll-a in Lake Huron using Sentinel-2 measurements

    Science.gov (United States)

    Chen, Jiang; Zhu, Weining; Tian, Yong Q.; Yu, Qian; Zheng, Yuhan; Huang, Litong

    2017-07-01

    Colored dissolved organic matter (CDOM) and chlorophyll-a (Chla) are important water quality parameters and play crucial roles in aquatic environment. Remote sensing of CDOM and Chla concentrations for inland lakes is often limited by low spatial resolution. The newly launched Sentinel-2 satellite is equipped with high spatial resolution (10, 20, and 60 m). Empirical band ratio models were developed to derive CDOM and Chla concentrations in Lake Huron. The leave-one-out cross-validation method was used for model calibration and validation. The best CDOM retrieval algorithm is a B3/B5 model with accuracy coefficient of determination (R2)=0.884, root-mean-squared error (RMSE)=0.731 m-1, relative root-mean-squared error (RRMSE)=28.02%, and bias=-0.1 m-1. The best Chla retrieval algorithm is a B5/B4 model with accuracy R2=0.49, RMSE=9.972 mg/m3, RRMSE=48.47%, and bias=-0.116 mg/m3. Neural network models were further implemented to improve inversion accuracy. The applications of the two best band ratio models to Sentinel-2 imagery with 10 m×10 m pixel size presented the high potential of the sensor for monitoring water quality of inland lakes.

  5. Landscape-Level Associations of Wintering Waterbird Diversity and Abundance from Remotely Sensed Wetland Characteristics of Poyang Lake

    Directory of Open Access Journals (Sweden)

    Iryna Dronova

    2016-05-01

    Full Text Available Poyang Lake, the largest freshwater wetland in China, provides critical habitat for wintering waterbirds from the East Asian Flyway; however, landscape drivers of non-uniform bird diversity and abundance are not yet well understood. Using a winter 2006 waterbird survey, we examined the relationships among metrics of bird community diversity and abundance and landscape characteristics of 51 wetland sub-lakes derived by an object-based classification of Landsat satellite data. Relative importance of predictors and their sets was assessed using information-theoretic model selection and the Akaike Information Criterion. Ordinary least squares regression models were diagnosed and corrected for spatial autocorrelation using spatial autoregressive lag and error models. The strongest and most consistent landscape predictors included Normalized Difference Vegetation Index for mudflat (negative effect and emergent grassland (positive effect, total sub-lake area (positive effect, and proportion of submerged vegetation (negative effect. Significant spatial autocorrelation in linear regression was associated with local clustering of response and predictor variables, and should be further explored for selection of wetland sampling units and management of protected areas. Overall, results corroborate the utility of remote sensing to elucidate potential indicators of waterbird diversity that complement logistically challenging ground observations and offer new hypotheses on factors underlying community distributions.

  6. REMOTE DETENTION OF INVASIVE AND OPPORTUNISTIC PLANT SPECIES IN GREAT LAKES COASTAL WETLANDS

    Science.gov (United States)

    Invasive and opportunistic plant species have been associated with wetland disturbance. Increases in the abundance of plant species such as common reed (Phragmites australis) in coastal Great Lakes wetlands are hypothesized to occur with shifts toward drier hydrologic regimes, fr...

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

    Science.gov (United States)

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

    2014-05-01

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

  8. Satellite remote sensing for modeling and monitoring of water quality in the Great Lakes

    Science.gov (United States)

    Coffield, S. R.; Crosson, W. L.; Al-Hamdan, M. Z.; Barik, M. G.

    2017-12-01

    Consistent and accurate monitoring of the Great Lakes is critical for protecting the freshwater ecosystems, quantifying the impacts of climate change, understanding harmful algal blooms, and safeguarding public health for the millions who rely on the Lakes for drinking water. While ground-based monitoring is often hampered by limited sampling resolution, satellite data provide surface reflectance measurements at much more complete spatial and temporal scales. In this study, we implemented NASA data from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Aqua satellite to build robust water quality models. We developed and validated models for chlorophyll-a, nitrogen, phosphorus, and turbidity based on combinations of the six MODIS Ocean Color bands (412, 443, 488, 531, 547, and 667nm) for 2003-2016. Second, we applied these models to quantify trends in water quality through time and in relation to changing land cover, runoff, and climate for six selected coastal areas in Lakes Michigan and Erie. We found strongest models for chlorophyll-a in Lake Huron (R2 = 0.75), nitrogen in Lake Ontario (R2=0.66), phosphorus in Lake Erie (R2=0.60), and turbidity in Lake Erie (R2=0.86). These offer improvements over previous efforts to model chlorophyll-a while adding nitrogen, phosphorus, and turbidity. Mapped water quality parameters showed high spatial variability, with nitrogen concentrated largely in Superior and coastal Michigan and high turbidity, phosphorus, and chlorophyll near urban and agricultural areas of Erie. Temporal analysis also showed concurrence of high runoff or precipitation and nitrogen in Lake Michigan offshore of wetlands, suggesting that water quality in these areas is sensitive to changes in climate.

  9. Remote collection of microorganisms at two depths in a freshwater lake using an unmanned surface vehicle (USV

    Directory of Open Access Journals (Sweden)

    Craig Powers

    2018-01-01

    Full Text Available Microorganisms are ubiquitous in freshwater aquatic environments, but little is known about their abundance, diversity, and transport. We designed and deployed a remote-operated water-sampling system onboard an unmanned surface vehicle (USV, a remote-controlled boat to collect and characterize microbes in a freshwater lake in Virginia, USA. The USV collected water samples simultaneously at 5 and 50 cm below the surface of the water at three separate locations over three days in October, 2016. These samples were plated on a non-selective medium (TSA and on a medium selective for the genus Pseudomonas (KBC to estimate concentrations of culturable bacteria in the lake. Mean concentrations ranged from 134 to 407 CFU/mL for microbes cultured on TSA, and from 2 to 8 CFU/mL for microbes cultured on KBC. There was a significant difference in the concentration of microbes cultured on KBC across three sampling locations in the lake (P = 0.027, suggesting an uneven distribution of Pseudomonas across the locations sampled. There was also a significant difference in concentrations of microbes cultured on TSA across the three sampling days (P = 0.038, demonstrating daily fluctuations in concentrations of culturable bacteria. There was no significant difference in concentrations of microbes cultured on TSA (P = 0.707 and KBC (P = 0.641 across the two depths sampled, suggesting microorganisms were well-mixed between 5 and 50 cm below the surface of the water. About 1 percent (7/720 of the colonies recovered across all four sampling missions were ice nucleation active (ice+ at temperatures warmer than −10 °C. Our work extends traditional manned observations of aquatic environments to unmanned systems, and highlights the potential for USVs to understand the distribution and diversity of microbes within and above freshwater aquatic environments.

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

    Science.gov (United States)

    Ma, Long; Wu, Jinglu; Abuduwaili, Jilili

    2013-04-01

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

  11. Remote sensing data of SP Mountain and SP Lava flow in North-Central Arizona

    Science.gov (United States)

    Schaber, G.G.; Elachi, C.; Farr, T.G.

    1980-01-01

    Multifrequency airborne radar image data of SP Mountain [Official name of feature (U.S. Geological Survey, 1970)] and SP flow (and vicinity) in north-central Arizona were obtained in diverse viewing directions and direct and cross-polarization, then compared with surface and aerial photography, LANDSAT multispectral scanner data, airborne thermal infrared imagery, surface geology, and surface roughness statistics. The extremely blocky, basaltic andesite of SP flow is significantly brighter on direct-polarization K-band (0.9-cm wavelength) images than on cross-polarized images taken simultaneously. Conversely, for the longer wavelength (25 cm) L-band radar images, the cross-polarization image returns from SP flow are brighter than the direct-polarized image. This effect is explained by multiple scattering and the strong wavelength dependence of polarization effects caused by the rectilinear basaltic andesite scatters. Two distinct types of surface relief on SP flow, one extremely blocky, the other subdued, are found to be clearly discriminated on the visible and thermal wavelength images but are separable only on the longer wavelength L-band radar image data. The inability of the K- and X- (3-cm wavelength) band radars to portray the differences in roughness between the two SP flow surface units is attributed to the radar frequency dependence of the surface-relief scale, which, described as the Rayleigh criterion, represents the transition between quasispecular and primarily diffuse backscatter. ?? 1980.

  12. Effects of ultraviolet radiation and nutrients on the structure-function of phytoplankton in a high mountain lake.

    Science.gov (United States)

    Korbee, Nathalie; Carrillo, Presentación; Mata, M Teresa; Rosillo, Silvia; Medina-Sánchez, Juan Manuel; Figueroa, Félix L

    2012-06-01

    The combined effect of high solar ultraviolet radiation (UVR) and nutrient supply in a phytoplankton community of a high mountain lake is analyzed in a in situ experiment for 6 days with 2 × 2 factorial design. Interactive UVR × nutrient effects on structural and functional variables (algal biomass, chlorophyll a (chl a), primary production (PP), maximal electron transport rate (ETR(max)), and alkaline phosphatase activity (APA)), as well as stoichiometric ones (sestonic N per cell and N:P ratio) were found. Under non-nutrient enriched conditions, no deleterious effects of UVR on structural variables, PP, photosynthetic efficiency and ETR(max) were observed, whereas only particulate and total APA were affected by UVR. However, percentage excreted organic carbon (%EOC), dissolved APA and sestonic C and P per cell increased under UVR, leading to a decrease in algal C:P and N:P ratios. After nutrient enrichment, chl a, total algal biomass and PP were negatively affected by UVR whereas %EOC, ETR(max) and internal C, P and N content increased. We suggest that the mechanism of algal acclimation to UVR in this high UVR flux ecosystem seems to be related to the increase of internal algal P-content mediated by physiological mechanisms to save P and by a stimulatory UVR effect on dissolved extracellular APA. The mechanism involved in the unmasking effect of UVR after nutrient-enrichment may be the result of a greater sensitivity to UVR-induced cell damage, making the negative UVR effects more evident.

  13. Mercury biomagnification and the trophic structure of the ichthyofauna from a remote lake in the Brazilian Amazon

    International Nuclear Information System (INIS)

    Azevedo-Silva, Claudio Eduardo; Almeida, Ronaldo; Carvalho, Dario P.; Ometto, Jean P.H.B.; Camargo, Plínio B. de

    2016-01-01

    confirm that Hg biomagnifies through the food web of Puruzinho Lake ichthyofauna. The migratory species did not significantly change mercury biomagnification rate in Puruzinho Lake; however, they may play a relevant role in Hg transport. The biomagnification rate (TMS value) in Puruzinho Lake was higher than the average values for its latitude, being comparable to TMS values of temperate and polar systems (marine and freshwater environments). - Highlights: • Mercury biomagnified in food web of a remote Amazonian lake. • δ 13 C and δ 15 N values suggest multiple Hg sources in food web with 3 trophic levels. • We found similar Hg transfer efficiencies in pelagic and littoral food chains. • Migration may influence the trophic structure assessment performed with δ 15 N. • The migrating species did not significantly alter the biomagnification calculation.

  14. Monitoring Recent Fluctuations of the Southern Pool of Lake Chad Using Multiple Remote Sensing Data: Implications for Water Balance Analysis

    Directory of Open Access Journals (Sweden)

    Wenbin Zhu

    2017-10-01

    Full Text Available The drought episodes in the second half of the 20th century have profoundly modified the state of Lake Chad and investigation of its variations is necessary under the new circumstances. Multiple remote sensing observations were used in this paper to study its variation in the recent 25 years. Unlike previous studies, only the southern pool of Lake Chad (SPLC was selected as our study area, because it is the only permanent open water area after the serious lake recession in 1973–1975. Four satellite altimetry products were used for water level retrieval and 904 Landsat TM/ETM+ images were used for lake surface area extraction. Based on the water level (L and surface area (A retrieved (with coinciding dates, linear regression method was used to retrieve the SPLC’s L-A curve, which was then integrated to estimate water volume variations ( Δ V . The results show that the SPLC has been in a relatively stable phase, with a slight increasing trend from 1992 to 2016. On annual average scale, the increase rate of water level, surface area and water volume is 0.5 cm year−1, 0.14 km2 year−1 and 0.007 km3 year−1, respectively. As for the intra-annual variations of the SPLC, the seasonal variation amplitude of water level, lake area and water volume is 1.38 m, 38.08 km2 and 2.00 km3, respectively. The scatterplots between precipitation and Δ V indicate that there is a time lag of about one to two months in the response of water volume variations to precipitation, which makes it possible for us to predict Δ V . The water balance of the SPLC is significantly different from that of the entire Lake Chad. While evaporation accounts for 96% of the lake’s total water losses, only 16% of the SPLC’s losses are consumed by evaporation, with the other 84% offset by outflow.

  15. Water resources assessment in a poorly gauged mountainous catchment using a geographical information system and remote sensing

    Science.gov (United States)

    Shrestha, Roshan; Takara, Kaoru; Tachikawa, Yasuto; Jha, Raghu N.

    2004-11-01

    Water resources assessment, which is an essential task in making development plans managing water resources, is considerably difficult to do in a data-poor region. In this study, we attempted to conduct a quantitative water resources assessment in a poorly gauged mountainous catchment, i.e. the River Indrawati catchment (1233 km2) in Nepal. This catchment is facing problems such as dry-season water scarcity and water use conflicts. However, the region lacks the basic data that this study needs. The data needed are supplemented from field surveys and global data (e.g. GTOPO30 DEM data, LandsatTM data and MODIS NDVI data). The global data have significantly helped us to draw out the information needed for a number of water-use scenarios. These data helped us determine that the available water quantity is enough at present to address the dry-season problems. The situation is not much worse for the immediate future; however, the threat of drought is noticed in a future scenario in which resources are consumed extensively. The study uses a geographical information system and remotely sensed data analysis tools extensively. Utilization of modern tools and global data is found effective for investigating practical problems and for detecting important features of water resources, even though the catchment is poorly gauged.

  16. Remote sensing estimation of the total phosphorus concentration in a large lake using band combinations and regional multivariate statistical modeling techniques.

    Science.gov (United States)

    Gao, Yongnian; Gao, Junfeng; Yin, Hongbin; Liu, Chuansheng; Xia, Ting; Wang, Jing; Huang, Qi

    2015-03-15

    Remote sensing has been widely used for ater quality monitoring, but most of these monitoring studies have only focused on a few water quality variables, such as chlorophyll-a, turbidity, and total suspended solids, which have typically been considered optically active variables. Remote sensing presents a challenge in estimating the phosphorus concentration in water. The total phosphorus (TP) in lakes has been estimated from remotely sensed observations, primarily using the simple individual band ratio or their natural logarithm and the statistical regression method based on the field TP data and the spectral reflectance. In this study, we investigated the possibility of establishing a spatial modeling scheme to estimate the TP concentration of a large lake from multi-spectral satellite imagery using band combinations and regional multivariate statistical modeling techniques, and we tested the applicability of the spatial modeling scheme. The results showed that HJ-1A CCD multi-spectral satellite imagery can be used to estimate the TP concentration in a lake. The correlation and regression analysis showed a highly significant positive relationship between the TP concentration and certain remotely sensed combination variables. The proposed modeling scheme had a higher accuracy for the TP concentration estimation in the large lake compared with the traditional individual band ratio method and the whole-lake scale regression-modeling scheme. The TP concentration values showed a clear spatial variability and were high in western Lake Chaohu and relatively low in eastern Lake Chaohu. The northernmost portion, the northeastern coastal zone and the southeastern portion of western Lake Chaohu had the highest TP concentrations, and the other regions had the lowest TP concentration values, except for the coastal zone of eastern Lake Chaohu. These results strongly suggested that the proposed modeling scheme, i.e., the band combinations and the regional multivariate

  17. Developing Remote Sensing Products for Monitoring and Modeling Great Lakes Coastal Wetland Vulnerability to Climate Change and Land Use

    Science.gov (United States)

    Bourgeau-Chavez, L. L.; Miller, M. E.; Battaglia, M.; Banda, E.; Endres, S.; Currie, W. S.; Elgersma, K. J.; French, N. H. F.; Goldberg, D. E.; Hyndman, D. W.

    2014-12-01

    Spread of invasive plant species in the coastal wetlands of the Great Lakes is degrading wetland habitat, decreasing biodiversity, and decreasing ecosystem services. An understanding of the mechanisms of invasion is crucial to gaining control of this growing threat. To better understand the effects of land use and climatic drivers on the vulnerability of coastal zones to invasion, as well as to develop an understanding of the mechanisms of invasion, research is being conducted that integrates field studies, process-based ecosystem and hydrological models, and remote sensing. Spatial data from remote sensing is needed to parameterize the hydrological model and to test the outputs of the linked models. We will present several new remote sensing products that are providing important physiological, biochemical, and landscape information to parameterize and verify models. This includes a novel hybrid radar-optical technique to delineate stands of invasives, as well as natural wetland cover types; using radar to map seasonally inundated areas not hydrologically connected; and developing new algorithms to estimate leaf area index (LAI) using Landsat. A coastal map delineating wetland types including monocultures of the invaders (Typha spp. and Phragmites austrailis) was created using satellite radar (ALOS PALSAR, 20 m resolution) and optical data (Landsat 5, 30 m resolution) fusion from multiple dates in a Random Forests classifier. These maps provide verification of the integrated model showing areas at high risk of invasion. For parameterizing the hydrological model, maps of seasonal wetness are being developed using spring (wet) imagery and differencing that with summer (dry) imagery to detect the seasonally wet areas. Finally, development of LAI remote sensing high resolution algorithms for uplands and wetlands is underway. LAI algorithms for wetlands have not been previously developed due to the difficulty of a water background. These products are being used to

  18. Integrated Application of Remote Sensing, GIS and Hydrological Modeling to Estimate the Potential Impact Area of Earthquake-Induced Dammed Lakes

    Directory of Open Access Journals (Sweden)

    Bo Cao

    2017-10-01

    Full Text Available Dammed lakes are an important secondary hazard caused by earthquakes. They can induce further damage to nearby humans. Current hydrology calculation research on dammed lakes usually lacks spatial expressive ability and cannot accurately conduct impact assessment without the support of remote sensing, which obtains important characteristic information of dammed lakes. The current study aims to address the issues of the potential impact area estimate of earthquake-induced dammed lakes by combining remote sensing (RS, a geographic information system (GIS, and hydrological modeling. The Tangjiashan dammed lake induced by the Wenchuan earthquake was selected as the case for study. The elevation-versus-reservoir capacity curve was first calculated using the seed-growing algorithm based on digital elevation model (DEM data. The simulated annealing algorithm was applied to train the hydrological modeling parameters according to the historical hydrologic data. Then, the downstream water elevation variational process under different collapse capacity conditions was performed based on the obtained parameters. Finally, the downstream potential impact area was estimated by the highest water elevation values at different hydrologic sections. Results show that a flood with a collapse elevation of at least 680 m will impact the entire downstream region of Beichuan town. We conclude that spatial information technology combined with hydrological modeling can accurately predict and demonstrate the potential impact area with limited data resources. This paper provides a better guide for future immediate responses to dammed lake hazard mitigation.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Directory of Open Access Journals (Sweden)

    E. W. Helbling

    2013-02-01

    Full Text Available 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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

  4. Remote Sensing and Underwater Glider Observations of a Springtime Plume in Western Lake Superior

    Science.gov (United States)

    Plumes are commonly observed in satellite imagery of western Lake Superior following storm events, and represent a significant cross-shelf pathway for sediment and other constituents. However, their subsurface extent is poorly understood. This study reports results from plume ob...

  5. Changes of glacier lakes using multi-temporal remote sensing data: A case study from India

    Directory of Open Access Journals (Sweden)

    Kumar Rai Praveen

    2017-01-01

    Full Text Available The present study used the potential of Landsat multispectral data and ASTER-DEM data to identify the changes of glacier lakes in part of Chandra basin and surrounding of Himachal Pradesh of India from 1989 to 2013. The Barashigri, Chotashigri, Hamtahand Parvati glacier are the major glaciers within the area. The Landsat data of TM (1989 and 2009, ETM+ (2001 and OLI-TIRS (2013 sensors having different band combinations were analysed to monitor variation in the glacier lakes and area of glaciers and terminus whereas ASTER-DEM data was used for relief information. Glaciers terminus and glacial lakes were identified and mapped using false-colour composites (FCC with band combinations of red, near-infrared (NIR and shortwave infrared (SWIR, and a true-colour composite of red, green and NIR, of Landsat TM/ETM+ images and normalized difference water index (NDWI methods. It is observed that the number of lakes in the study area increased by 18.69% during the past 34 years while it was increased from 68 in 1989 to 89 in 2013. During the analysis, it is also found that the snow and glacier covered area within this period is also reduced from 1,317.39 to 1,125.59 km2.

  6. Water quality and remote sensing: A case study of Lake Naivasha, Kenya

    CSIR Research Space (South Africa)

    Majozi, NP

    2012-10-01

    Full Text Available validation gave an RSME 0.24 and MAE 20%. Atmospheric correction processors, MERIS Neural Network processors, and the ODESA software, were applied to MERIS images. Eutrophic Lakes was the most accurate at 490nm with MAE 43% and RSME 0.49. The Zeu maps show...

  7. Modeling river discharge and sediment transport in the Wax Lake-Atchafalaya basin with remote sensing parametrization.

    Science.gov (United States)

    Simard, M.; Liu, K.; Denbina, M. W.; Jensen, D.; Rodriguez, E.; Liao, T. H.; Christensen, A.; Jones, C. E.; Twilley, R.; Lamb, M. P.; Thomas, N. A.

    2017-12-01

    Our goal is to estimate the fluxes of water and sediments throughout the Wax Lake-Atchafalaya basin. This was achieved by parametrization of a set of 1D (HEC-RAS) and 2D (DELFT3D) hydrology models with state of the art remote sensing measurements of water surface elevation, water surface slope and total suspended sediment (TSS) concentrations. The model implementations are spatially explicit, simulating river currents, lateral flows to distributaries and marshes, and spatial variations of sediment concentrations. Three remote sensing instruments were flown simultaneously to collect data over the Wax Lake-Atchafalaya basin, and along with in situ field data. A Riegl Lidar was used to measure water surface elevation and slope, while the UAVSAR L-band radar collected data in repeat-pass interferometric mode to measure water level change within adjacent marshes and islands. These data were collected several times as the tide rose and fell. AVRIS-NG instruments measured water surface reflectance spectra, used to estimate TSS. Bathymetry was obtained from sonar transects and water level changes were recorded by 19 water level pressure transducers. We used several Acoustic Doppler Current Profiler (ADCP) transects to estimate river discharge. The remotely sensed measurements of water surface slope were small ( 1cm/km) and varied slightly along the channel, especially at the confluence with bayous and the intra-coastal waterway. The slope also underwent significant changes during the tidal cycle. Lateral fluxes to island marshes were mainly observed by UAVSAR close to the distributaries. The extensive remote sensing measurements showed significant disparity with the hydrology model outputs. Observed variations in water surface slopes were unmatched by the model and tidal wave propagation was much faster than gauge measurements. The slope variations were compensated for in the models by tuning local lateral fluxes, bathymetry and riverbed friction. Overall, the simpler 1D

  8. Geothermal constraints on enrichment of boron and lithium in salt lakes: An example from a river-salt lake system on the northern slope of the eastern Kunlun Mountains, China

    Science.gov (United States)

    Tan, Hongbing; Chen, Jun; Rao, Wenbo; Zhang, Wenjie; Zhou, Huifang

    2012-06-01

    Some rivers on the northern slope of the eastern Kunlun Mountains in the Qaidam Basin, China, show very high concentrations of boron and lithium. Correspondingly, the salt lakes fed by these rivers show an unusual enrichment of boron and lithium, and become an important economic resource. The origin of boron and lithium has long been debated. The aim of this study is to analyze the water chemistry and hydrogen and oxygen isotopic composition of river water to understand the unusual enrichment of boron and lithium in the salt lakes of the Qaidam Basin. Oxygen and hydrogen isotope data show that the source of river water in the winter and summer originates from the Kunlun Mountain ice and snow melt water, respectively. The water chemistry shows that boron and lithium contents are high but little variable with seasons in the Nalenggele River and Wutumeiren River waters. By contrast, other rivers have much lower lithium and boron contents. Moreover, the contents of B3+ and Li+ in the river loads or bed sands show little difference amongst the rivers. This indicates that removal by adsorption or input by surface rock weathering is not the main controlling factor of the B3+ and Li+ variation in the rivers. Rivers with high B3+ and Li+ content are chemically similar to geothermal waters in the Tibetan Plateau. In addition, the source area of the Nalenggele River is located in a collision zone of the Kunlun Mountains and Altun Mountains. Large and deep faults can serve as conduits for geothermal fluids. Thus, deep geothermal waters in the source area can easily migrate to the surface and discharge as springs feeding the rivers. They are an important source of B3+ and Li+ to the rivers. The abnormally high contents of B3+ and Li+ in the Nalenggele and Wutumeiren Rivers also suggest that the geothermal source area may be a future target for boron and lithium resources.

  9. Remote sensing for predicting potential habitats of Oncomelania hupensis in Hongze, Baima and Gaoyou lakes in Jiangsu province, China

    Directory of Open Access Journals (Sweden)

    Guo-Jing Yang

    2006-11-01

    Full Text Available Political and health sector reforms, along with demographic, environmental and socio-economic transformations in the face of global warming, could cause the re-emergence of schistosomiasis in areas where transmission has been successfully interrupted and its emergence in previously non-endemic areas in China. In the present study, we used geographic information systems and remote sensing techniques to predict potential habitats of Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum. Focussing on the Hongze, Baima and Gaoyou lakes in Jiangsu province in eastern China, we developed a model using the normalized difference vegetation index, a tasseled-cap transformed wetness index, and flooding areas to predict snail habitats at a small scale. Data were extracted from two Landsat images, one taken during a typical dry year and the other obtained three years later during a flooding event. An area of approximately 163.6 km2 was predicted as potential O. hupensis habitats around the three lakes, which accounts for 4.3% of the estimated snail habitats in China. In turn, these predicted snail habitats are risk areas for transmission of schistosomiasis, and hence illustrate the scale of the possible impact of climate change and other ecological transformations. The generated risk map can be used by health policy makers to guide mitigation policies targetting the possible spread of O. hupensis, and with the aim of containing the transmission of S. japonicum.

  10. Monitoring of Vegetation Impact Due to Trampling on Cadillac Mountain Summit Using High Spatial Resolution Remote Sensing Data Sets

    Science.gov (United States)

    Kim, Min-Kook; Daigle, John J.

    2012-11-01

    Cadillac Mountain—the highest peak along the eastern seaboard of the United States—is a major tourist destination in Acadia National Park, Maine. Managing vegetation impact due to trampling on the Cadillac Mountain summit is extremely challenging because of the large number of visitors and the general open nature of landscape in this fragile subalpine environmental setting. Since 2000, more intensive management strategies—based on placing physical barriers and educational messages for visitors—have been employed to protect threatened vegetation, decrease vegetation impact, and enhance vegetation recovery in the vicinity of the summit loop trail. The primary purpose of this study was to evaluate the effect of the management strategies employed. For this purpose, vegetation cover changes between 2001 and 2007 were detected using multispectral high spatial resolution remote sensing data sets. A normalized difference vegetation index was employed to identify the rates of increase and decrease in the vegetation areas. Three buffering distances (30, 60, and 90 m) from the edges of the trail were used to define multiple spatial extents of the site, and the same spatial extents were employed at a nearby control site that had no visitors. No significant differences were detected between the mean rates of vegetation increase and decrease at the experimental site compared with a nearby control site in the case of a small spatial scale (≤30 m) comparison (in all cases P > 0.05). However, in the medium (≤60 m) and large (≤90 m) spatial scales, the rates of increased vegetation were significantly greater and rates of decreased vegetation significantly lower at the experimental site compared with the control site (in all cases P Management implications are explored in terms of the spatial strategies used to decrease the impact of trampling on vegetation.

  11. Alpine hydropower schemes and their 'remote influence' on lakes and rivers downstream

    International Nuclear Information System (INIS)

    Wuest, A.

    2003-01-01

    This article discusses the effect that alpine dams and reservoirs have on lakes and rivers in the lowlands. Not only the contribution of Swiss alpine hydropower installations to Switzerland's electricity generation capacity is mentioned, but also the way they 'export' ecological deficits to lower-lying regions. Examples of this are quoted, including, for example, the filtering-out of around 50% of water-borne particles in the river Rhone by the dams in its catchment area. The consequences of such effects for the ecology of lakes and rivers are discussed. Further examples of how the alpine dams hold back nutrients and regulate the flow and temperature of rivers are given and the resulting ecological effects are commented on

  12. Quantifying Streamflow Variations in Ungauged Lake Basins by Integrating Remote Sensing and Water Balance Modelling: A Case Study of the Erdos Larus relictus National Nature Reserve, China

    Directory of Open Access Journals (Sweden)

    Kang Liang

    2017-06-01

    Full Text Available Hydrological predictions in ungauged lakes are one of the most important issues in hydrological sciences. The habitat of the Relict Gull (Larus relictus in the Erdos Larus relictus National Nature Reserve (ELRNNR has been seriously endangered by lake shrinkage, yet the hydrological processes in the catchment are poorly understood due to the lack of in-situ observations. Therefore, it is necessary to assess the variation in lake streamflow and its drivers. In this study, we employed the remote sensing technique and empirical equation to quantify the time series of lake water budgets, and integrated a water balance model and climate elasticity method to further examine ELRNNR basin streamflow variations from1974 to 2013. The results show that lake variations went through three phases with significant differences: The rapidly expanding sub-period (1974–1979, the relatively stable sub-period (1980–1999, and the dramatically shrinking sub-period (2000–2013. Both climate variation (expressed by precipitation and evapotranspiration and human activities were quantified as drivers of streamflow variation, and the driving forces in the three phases had different contributions. As human activities gradually intensified, the contributions of human disturbances on streamflow variation obviously increased, accounting for 22.3% during 1980–1999 and up to 59.2% during 2000–2013. Intensified human interferences and climate warming have jointly led to the lake shrinkage since 1999. This study provides a useful reference to quantify lake streamflow and its drivers in ungauged basins.

  13. Airborne remote sensing of water constituents at Lake Constance; Flugzeuggestuetzte Fernerkundung von Wasserinhaltsstoffen im Bodensee

    Energy Technology Data Exchange (ETDEWEB)

    Heege, T.

    2000-12-01

    An inversion scheme for the retrieval of water constituents in case II waters from airborne multispectral scanner data is presented. This method includes modules for the calculation of aerosol types and contents, for the correction of sun glitter radiances and for the atmospheric correction of the image data. In 1996 extensive measurements were performed to determine the optical properties in Lake Constance. In combination with data collected through many years within a project of the German Research Foundation (SFB 248), for the first time a data set of inherent optical parameters being specific for typical substances in the Lake could be established. By means of the inversions scheme and the specific optical properties, geo-coded maps of suspended matter and chlorophyll were calculated from the multispectral airborne measurements above Lake Constance. (orig.) [German] Zur Berechnung von Wasserinhaltsstoffen aus Daten flugzeuggetragener Multispektralscanner wird ein Inversionsverfahren vorgestellt. Es beinhaltet die Bestimmung von Aerosoltypen und -konzentrationen, die bildpunktweise Korrektur von Oberflaechenreflexionen des Sonnenlichtes und die Atmosphaerenkorrektur von Fernerkundungsdaten. Zur Erfassung der optischen Groessen im Wasser wurden umfangreiche Messkampagnen am Bodensee durchgefuehrt. Zusammen mit vieljaehrigen Datensaetzen des DFG-Sonderforschungsbereichs 248 wird damit erstmalig ein vollstaendiger Satz der inhaerenten optischen stoffspezifischen Groessen fuer den Bodensee bestimmt. Zur Validation werden diese anhand von verschiedenen Modellen zur Verknuepfung der inhaerenten Streu- und Absorptionskoeffizienten mit den messbaren Groessen Extinktion und diffuse Reflexion auf Konsistenz geprueft. Aus Befliegungen mit dem Multispektralscanner Daedalus werden mit den vorgestellten Verfahren und optischen Groessen georeferenzierte Verteilungskarten von Schwebstoff und Phytoplankton-Pigmenten berechnet. (orig.)

  14. Looking Back to Move Forward: Collaborative Planning to Revise the Green Mountain and Finger Lakes National Forests Land and Resource Management Plans

    Directory of Open Access Journals (Sweden)

    Michael J Dockry

    2015-07-01

    Full Text Available The United States Department of Agriculture Forest Service (Forest Service manages 154 national forests and 20 grasslands in 44 states and Puerto Rico. National Forest Land and Resource Management Plans (forest plans form the basis for land and resource management of national forests in the United States. For more than a decade the Forest Service has been attempting to incorporate innovative, collaborative public involvement strategies into the process for revising forest plans. In 2012 and 2015 the Forest Service codified new regulations for developing, revising, and amending forest plans. Collaboration and public involvement are explicit goals of the new regulations. This paper briefly reviews the literature on collaborative planning on national forests and explores a successful collaborative planning process used by the Green Mountain and Finger Lakes National Forests, located in Vermont and New York respectively, to develop their 2006 forest plans. This paper shows how the Green Mountain and Finger Lakes National Forests developed parallel public and internal collaborative processes to build trust, relationships, and partnership, and discusses the implications for process design, capacity building, and facilitating agreements. By looking back at this successful case of collaborative forest planning, key lessons can provide ideas for developing collaborative processes for future planning efforts.

  15. Predictive Mapping of Dwarf Shrub Vegetation in an Arid High Mountain Ecosystem Using Remote Sensing and Random Forests

    Directory of Open Access Journals (Sweden)

    Kim André Vanselow

    2014-07-01

    Full Text Available In many arid mountains, dwarf shrubs represent the most important fodder and firewood resources; therefore, they are intensely used. For the Eastern Pamirs (Tajikistan, they are assumed to be overused. However, empirical evidence on this issue is lacking. We aim to provide a method capable of mapping vegetation in this mountain desert. We used random forest models based on remote sensing data (RapidEye, ASTER GDEM and 359 plots to predictively map total vegetative cover and the distribution of the most important firewood plants, K. ceratoides and A. leucotricha. These species were mapped as present in 33.8% of the study area (accuracy 90.6%. The total cover of the dwarf shrub communities ranged from 0.5% to 51% (per pixel. Areas with very low cover were limited to the vicinity of roads and settlements. The model could explain 80.2% of the total variance. The most important predictor across the models was MSAVI2 (a spectral vegetation index particularly invented for low-cover areas. We conclude that the combination of statistical models and remote sensing data worked well to map vegetation in an arid mountainous environment. With this approach, we were able to provide tangible data on dwarf shrub resources in the Eastern Pamirs and to relativize previous reports about their extensive depletion.

  16. Experimental Evaluation of Performance of Constant Power Prime-Mover Driven Isolated 3-φ SEIG for Pico-Hydro Power Generation System in Remote Mountainous Region of Himalayas

    Directory of Open Access Journals (Sweden)

    Rathore Umesh C.

    2016-01-01

    Full Text Available This paper presents the experimental evaluation of the performance of 3-φ self-excited induction generator (SEIG suitable for pico-hydro power generation system feeding domestic load in remote mountainous region. The use of induction generators is most suitable for renewable energy conversion systems due to their enormous advantages over conventional synchronous generators. Important features of induction generators include the simplicity in construction, ruggedness, simplified control, ease in maintenance and small size per generated kW. The performance characteristics of 3-φ SEIG feeding isolated load are evaluated using MATLAB-Simulink model based on the prevalent renewable energy sources inputs and loading conditions in mountainous terrain of Himalayas. The results are validated using an experimental set-up comprising of 3-φ, 3 HP induction motor run as 3- φ induction generator driven by 5HP, 4-pole DC shunt motor acting as prime-mover.

  17. Remote sensing of the surface layer dynamics of a stratified lake

    Science.gov (United States)

    Steissberg, Todd Eugene

    Physical processes, such as upwelling, circulation, and small-scale eddies, affect aquatic ecosystem functioning, controlling nutrient and light availability and pollutant transport in inland and coastal waters. These processes can be characterized and tracked across time and space using a combination of thermal infrared and reflective-solar (visible light) satellite measurements. Thermal gradients, created and altered by physical processes, facilitate daytime and nighttime detection and tracking of upwelling fronts, surface jets, basin-scale gyres, and small-scale eddies. Similarly, sunglint patterns in reflective-solar satellite measurements are altered by internal waves, current shear, and rotation, improving delineation of fronts, jets, and eddies, and determination of transport direction or rotational characteristics. This study applied thermal infrared and reflective-solar satellite images and field measurements, collected across multiple spatial and temporal scales, to characterize upwelling, circulation, and eddies at Lake Tahoe, California-Nevada. This included developing a novel technique to improve the quality of moderate-resolution satellite temperature data, creating filtered, calibrated Water Skin Temperature (WST) maps that clearly delineate thermal features, while preserving nearshore data and temperature accuracy. Time series of filtered WST maps acquired by two moderate-resolution satellite sensors were used to track up-welling fronts and jets, which can recur at moderate wind speeds when wind forcing is in phase with internal wave motion. High-resolution temperature and sunglint maps were used to characterize several, small-scale "spiral eddies" at Lake Tahoe. These features, although common in the ocean, have not been documented before in lakes. Satellite measurements showed spiral eddies form along thermal fronts and shear zones at Lake Tahoe, rotating predominantly cyclonically, as in the ocean, with sub-inertial periods longer than 21 hours

  18. Causes and effects of long periods of ice cover on a remote high Alpine lake

    Directory of Open Access Journals (Sweden)

    Michael STURM

    2000-09-01

    Full Text Available The response of the physical and chemical limnology of Hagelseewli (2339 m a.s.l. to local meteorological forcing was investigated from 1996 to 1998 using an automatic weather station, thermistor chains, water samples and sediment traps. On-site meteorological measurements revealed the paramount importance of local topographic shading for the limnology of the lake. A high cliff to the south diminishes incident radiation by 15% to 90%, resulting in a long period of ice cover. Hence, the spring and summer seasons are extremely condensed, allowing only about 2 months per year for mixing, oxygen uptake, nutrient inflow, water exchange and phytoplankton growth. Regular measurements of water temperature, chemistry and diatom composition show that Hagelseewli responds very rapidly to changes in nutrient concentrations and light conditions. This response is restricted mainly to an extremely short productivity pulse, which takes place as soon as the lake is completely free of ice. Ice-free conditions are indicated by the occurrence of planktonic diatoms. In contrast to most low-altitude lakes, maximum productivity occurs in the middle of the water column (6-9 m, where first light, and then soluble reactive phosphorus (SRP, are the limiting factors. During the period of thawing, large amounts of ammonium enter the lake. Nevertheless, allochthonous nutrient input is not important because SRP, the limiting nutrient for algal growth, originates from the sediments. Water chemistry data and data from sediment traps show that, although autochthonous calcite precipitation does occur, the calcite crystals are redissolved completely in the bottom waters during the extended period of ice cover. Thus, the most important factor for changes in the nutrient budget, primary production and preservation of calcite is the bottom water oxygen status, which is governed by the occurrence of an ice-free period. We hypothesise that the duration of the ice-free period is of

  19. A 15,400-year record of environmental magnetic variations in sub-alpine lake sediments from the western Nanling Mountains in South China: Implications for palaeoenvironmental changes

    Science.gov (United States)

    Zhong, Wei; Wei, Zhiqiang; Shang, Shentan; Ye, Susu; Tang, Xiaowen; Zhu, Chan; Xue, Jibin; Ouyang, Jun; Smol, John P.

    2018-04-01

    A detailed environmental magnetic investigation has been performed on a sub-alpine sedimentary succession deposited over the past 15,400 years in Daping Swamp in the western Nanling Mountains of South China. Magnetic parameters reveal that fine grains of pseudo-single domain (PSD) magnetite or titanomagnetite are the dominant magnetic minerals in the lake sediments and surface soils collected from the catchment, which suggests that magnetic minerals in lake sediments mainly originated from surface soil erosion of the catchment. Variation of surface runoff caused by rainfall is interpreted as the main process for transportation of weathered soils into the lake. In the Last Deglacial period (LGP, 15,400-11,500 cal a BP), the influx of magnetic minerals of detrital material may have been significantly affected by the severe dry and cold conditions of the Last Glacial Maximum. Stabilised conditions of the catchment associated with increased vegetation coverage (e.g., 8000-4500 and 2500-1000 cal a BP) limited the input of magnetic minerals. Intensive soil erosion caused by increased human activity may have given rise to abnormal increases in multiple magnetic parameters after 1000 cal a BP. Because changes in runoff and vegetation coverage are closely related to Asian summer monsoon (ASM) intensity, the sedimentary magnetism of Daping Swamp provides another source of information to investigate the evolution of the ASM.

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

    Science.gov (United States)

    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.

  1. Mercury biomagnification and the trophic structure of the ichthyofauna from a remote lake in the Brazilian Amazon

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo-Silva, Claudio Eduardo, E-mail: ceass@biof.ufrj.br [Laboratório de Radioisótopos Eduardo Penna, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Cidade Universitária, Av. Carlos Chagas Filho s/n, bloco G, Sala 60, Subsolo, Ilha do Fundão, Rio de Janeiro, RJ (Brazil); Almeida, Ronaldo [Instituto Natureza e Cultura, Universidade Federal do Amazonas, Rua 1 de Maio. Colegiado de Ciências Agrárias, Benjamin Constant, Colônia, AM (Brazil); Carvalho, Dario P. [Laboratório de Radioisótopos Eduardo Penna, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Cidade Universitária, Av. Carlos Chagas Filho s/n, bloco G, Sala 60, Subsolo, Ilha do Fundão, Rio de Janeiro, RJ (Brazil); Ometto, Jean P.H.B. [Instituto Nacional de Pesquisas Espaciais, Centro de Ciências do Sistema Terrestre, Avenida dos Astronautas, 1758, Jardim da Granja, São José dos Campos, SP (Brazil); Camargo, Plínio B. de [Laboratório de Ecologia Isotópica, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Avenida Centenário, 303, São Dimas, Piracicaba, SP (Brazil); and others

    2016-11-15

    . These findings confirm that Hg biomagnifies through the food web of Puruzinho Lake ichthyofauna. The migratory species did not significantly change mercury biomagnification rate in Puruzinho Lake; however, they may play a relevant role in Hg transport. The biomagnification rate (TMS value) in Puruzinho Lake was higher than the average values for its latitude, being comparable to TMS values of temperate and polar systems (marine and freshwater environments). - Highlights: • Mercury biomagnified in food web of a remote Amazonian lake. • δ{sup 13}C and δ{sup 15}N values suggest multiple Hg sources in food web with 3 trophic levels. • We found similar Hg transfer efficiencies in pelagic and littoral food chains. • Migration may influence the trophic structure assessment performed with δ{sup 15}N. • The migrating species did not significantly alter the biomagnification calculation.

  2. Large drainages from short-lived glacial lakes in the Teskey Range, Tien Shan Mountains, Central Asia

    Science.gov (United States)

    Narama, Chiyuki; Daiyrov, Mirlan; Duishonakunov, Murataly; Tadono, Takeo; Sato, Hayato; Kääb, Andreas; Ukita, Jinro; Abdrakhmatov, Kanatbek

    2018-04-01

    Four large drainages from glacial lakes occurred during 2006-2014 in the western Teskey Range, Kyrgyzstan. These floods caused extensive damage, killing people and livestock as well as destroying property and crops. Using satellite data analysis and field surveys of this area, we find that the water volume that drained at Kashkasuu glacial lake in 2006 was 194 000 m3, at western Zyndan lake in 2008 was 437 000 m3, at Jeruy lake in 2013 was 182 000 m3, and at Karateke lake in 2014 was 123 000 m3. Due to their subsurface outlet, we refer to these short-lived glacial lakes as the tunnel-type, a type that drastically grows and drains over a few months. From spring to early summer, these lakes either appear, or in some cases, significantly expand from an existing lake (but non-stationary), and then drain during summer. Our field surveys show that the short-lived lakes form when an ice tunnel through a debris landform gets blocked. The blocking is caused either by the freezing of stored water inside the tunnel during winter or by the collapse of ice and debris around the ice tunnel. The draining then occurs through an opened ice tunnel during summer. The growth-drain cycle can repeat when the ice-tunnel closure behaves like that of typical supraglacial lakes on debris-covered glaciers. We argue here that the geomorphological characteristics under which such short-lived glacial lakes appear are (i) a debris landform containing ice (ice-cored moraine complex), (ii) a depression with water supply on a debris landform as a potential lake basin, and (iii) no visible surface outflow channel from the depression, indicating the existence of an ice tunnel. Applying these characteristics, we examine 60 depressions (> 0.01 km2) in the study region and identify here 53 of them that may become short-lived glacial lakes, with 34 of these having a potential drainage exceeding 10 m3 s-1 at peak discharge.

  3. Large drainages from short-lived glacial lakes in the Teskey Range, Tien Shan Mountains, Central Asia

    Directory of Open Access Journals (Sweden)

    C. Narama

    2018-04-01

    Full Text Available Four large drainages from glacial lakes occurred during 2006–2014 in the western Teskey Range, Kyrgyzstan. These floods caused extensive damage, killing people and livestock as well as destroying property and crops. Using satellite data analysis and field surveys of this area, we find that the water volume that drained at Kashkasuu glacial lake in 2006 was 194 000  m3, at western Zyndan lake in 2008 was 437 000 m3, at Jeruy lake in 2013 was 182 000 m3, and at Karateke lake in 2014 was 123 000 m3. Due to their subsurface outlet, we refer to these short-lived glacial lakes as the tunnel-type, a type that drastically grows and drains over a few months. From spring to early summer, these lakes either appear, or in some cases, significantly expand from an existing lake (but non-stationary, and then drain during summer. Our field surveys show that the short-lived lakes form when an ice tunnel through a debris landform gets blocked. The blocking is caused either by the freezing of stored water inside the tunnel during winter or by the collapse of ice and debris around the ice tunnel. The draining then occurs through an opened ice tunnel during summer. The growth–drain cycle can repeat when the ice-tunnel closure behaves like that of typical supraglacial lakes on debris-covered glaciers. We argue here that the geomorphological characteristics under which such short-lived glacial lakes appear are (i a debris landform containing ice (ice-cored moraine complex, (ii a depression with water supply on a debris landform as a potential lake basin, and (iii no visible surface outflow channel from the depression, indicating the existence of an ice tunnel. Applying these characteristics, we examine 60 depressions (> 0.01 km2 in the study region and identify here 53 of them that may become short-lived glacial lakes, with 34 of these having a potential drainage exceeding 10 m3 s−1 at peak discharge.

  4. Integrated Remote Sensing and Geophysical Investigations of the Geodynamic Activities at Lake Magadi, Southern Kenyan Rift

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    Akinola Adesuji Komolafe

    2012-01-01

    Full Text Available The tectonic lineaments and thermal structure of Lake Magadi, southern Kenyan rift system, were investigated using ASTER data and geophysical methods. Five N-S faults close to known hot springs were identified for geoelectric ground investigation. Aeromagnetic data were employed to further probe faults at greater depths and determine the Curie-point depth. Results indicate a funnel-shaped fluid-filled (mostly saline hydrothermal zone with relatively low resistivity values of less than 1 Ω-m, separated by resistive structures to the west and east, to a depth of 75 m along the resistivity profiles. There was evidence of saline hydrothermal fluid flow toward the surface through the fault splays. The observed faults extend from the surface to a depth of 7.5 km and are probably the ones that bound the graben laterally. They serve as major conduits for the upward heat flux in the study area. The aeromagnetics spectral analysis also revealed heat source emplacement at a depth of about 12 km. The relative shallowness implies a high geothermal gradient evidenced in the surface manifestations of hot springs along the lake margins. Correlation of the heat source with the hypocenters showed that the seismogenetic zone exists directly above the magmatic intrusion, forming the commencement of geodynamic activities.

  5. Mental health and burnout in primary and secondary school teachers in the remote mountain areas of Guangdong Province in the People's Republic of China

    Directory of Open Access Journals (Sweden)

    Zhang L

    2014-01-01

    Full Text Available Lulu Zhang,1 Jingping Zhao,1 Huaqing Xiao,3 Hongbo Zheng,2 Yaonan Xiao,3 Miaoyang Chen,3 Dingling Chen31Mental Health Institute of the Second Xiangya Hospital, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan, 2Department of Psychiatry, Guangzhou Brain Hospital, Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 3Department of Psychiatry, Luoding Dagang Hospital, Luoding, Guangdong, People's Republic of ChinaBackground: A growing number of studies have shown that education is a work context in which professionals (teachers seem likely to suffer from burnout that may be associated with low levels of mental health. Although there is a demonstrated need to improve the mental health and burnout levels among teachers, little is known about their mental health status, particularly with respect to graduating class teachers in remote mountain areas with undeveloped economies. The purpose of this study was to survey mental health and burnout among graduating class teachers in remote mountain areas and to examine the influence of moderating variables.Methods: We conducted a multilevel analysis of 590 graduating class teachers from 42 primary and secondary schools in remote mountain areas of Guangdong province in the People's Republic of China. The outcome variable of self-reported mental health was measured by the Symptom Checklist-90 (SCL-90, and burnout was measured by the Chinese Maslach Burnout Inventory for primary and secondary school teachers.Results: The status of both mental health and burnout among the respondents was significantly more troubling than the national norm used as a reference (P<0.05 or P<0.01. Each factor in the SCL-90 had a significant correlation with burnout (P<0.01. All factors of the SCL-90 were entered into the regression equation for each dimension of burnout (P<0.01. The factor having the greatest impact on emotional exhaustion and

  6. Investigating the causality of changes in the landscape pattern of Lake Urmia basin, Iran using remote sensing and time series analysis.

    Science.gov (United States)

    Mehrian, Majid Ramezani; Hernandez, Raul Ponce; Yavari, Ahmad Reza; Faryadi, Shahrzad; Salehi, Esmaeil

    2016-08-01

    Lake Urmia is the second largest hypersaline lake in the world in terms of surface area. In recent decades, the drop in water level of the lake has been one of the most important environmental issues in Iran. At present, the entire basin is threatened due to abrupt decline of the lake's water level and the consequent increase in salinity. Despite the numerous studies, there is still an ambiguity about the main cause of this environmental crisis. This paper is an attempt to detect the changes in the landscape structure of the main elements of the whole basin using remote sensing techniques and analyze the results against climate data with time series analysis for the purpose of achieving a more clarified illustration of processes and trends. Trend analysis of the different affecting factors indicates that the main cause of the drastic dry out of the lake is the huge expansion of irrigated agriculture in the basin between 1999 and 2014. The climatological parameters including precipitation and temperature cannot be the main reasons for reduced water level in the lake. The results show how the increase in irrigated agricultural area without considering the water resources limits can lead to a regional disaster. The approach used in this study can be a useful tool to monitor and assess the causality of environmental disaster.

  7. Space distribution, volume and structure of lodging facilities in the mountains of Slovenia: Case studies of the Bled lake, Bohinj, Bohinjska Bistrica, and Bovec

    Directory of Open Access Journals (Sweden)

    Vujko Aleksandra

    2012-01-01

    Full Text Available For the purpose of the assessment of the mountain tourism in the region, the authors chose the mountain Triglav ( Slovenia, and some of the most visited destinations on the mountain, in relation to the speed of reaching the necessary level of service quality, while keeping in mind that, twenty years ago, Slovenia was a part of Yugoslavia, just like Serbia. Slovenia has developed its own standards for defining specific areas suitable for the development of sports and recreational tourism. Such destinations are well marked and labeled; there are entire systems of bike route maps, bike and hiking trails, as well as the additional opportunities for engaging in complementary activities within certain sections (horseback riding, paintball, paragliding, etc.. Destinations have thematically arranged accommodation facilities, adapted to the requirements of sports and recreational tourists, whether it refers to hotels, campsites and tourist farms, they have well-trained staff (tour guide; in each destination, there are points where tourists can rent a bike and service it. In this sense, the aim of the paper is to show the condition of hotel offer for the Bled Lake, Bohinj, Bohinjska Bistrica, and Bovec, and the purpose of this paper is to exploit the situation observed for the development of the concrete innovative projects, which will elaborate a system of partnership that would contribute to sustainable development, encouraging entrepreneurship and a greater number of tourists on the mountains in Serbia. The methodology comprised field research and data collection through direct examination of the various managers of different hotel establishments, and tourism organizations of municipalities, various sport clubs, Slovenian societies and associations. The benchmark analysis was also used in order to compare the state of accommodation facilities with storage capacities in Serbia, with the aim of improving the state of accommodation capacities in Serbia.

  8. Mobilizing citizen science to build human and environmental resilience: a synthesis study of four remote mountain communities

    Science.gov (United States)

    Zulkafli, Zed; Buytaert, Wouter; Karpouzoglou, Timothy; Dewulf, Art; Gurung, Praju; Regmi, Santosh; Pandeya, Bhopal; Isaeva, Aiganysh; Mamadalieva, Zuura; Perez, Katya; Alemie, Tilashwork C.; Grainger, Sam; Clark, Julian; Hannah, David M.

    2015-04-01

    Communities that are the most vulnerable to environmental change and hazards, also tend to be those with the least institutional and financial resilience and capacity to cope with consequent impacts. Relevant knowledge generation is a key requisite for empowering these communities and developing adaptation strategies. Technological innovations in data collection, availability, processing, and exchange, are creating new opportunities for knowledge co-generation that may benefit vulnerable communities and bridge traditional knowledge divides. The use of open, web-based technologies and ICT solutions such as mobile phone apps is particularly promising in this regard, because they allow for participation of communities bypassed by traditional mechanisms. Here, we report on efforts to implement such technologies in a citizen science context. We focus on the active engagement of multiple actors (international and local scientists, government officials, NGOs, community associations, and individuals) in the entire process of the research. This ranges from problem framing, to identifying local monitoring needs, to determining the mode of exchange and forms of knowledge relevant for improving resilience related to water dependency. We present 4 case studies in arid, remote mountain regions of Nepal, the Kyrgyz Republic, Peru, and Ethiopia. In these regions, livelihoods depend on the water and soil systems undergoing accelerated degradation from extreme climates, poor agricultural management practices, and changing environmental conditions. However, information on the interlinkages of these processes with people's livelihoods is typically poor and there lies the opportunity for identifying novel forms of joint-creation and sharing of knowledge. Using a centrally-coordinated but locally-adaptable methodological framework comprising of field visits, systematic reviews of white and grey literature, focus group discussions, household questionnaires, semi-structured interviews

  9. Spatial dynamics of thermokarst and thermo-erosion at lakes and ponds in North Siberia and Northwest Alaska using high-resolution remote sensing

    Science.gov (United States)

    Grosse, G.; Tillapaugh, M.; Romanovsky, V. E.; Walter, K. M.; Plug, L. J.

    2008-12-01

    Formation, growth, and drainage of thermokarst lakes in ice-rich permafrost deposits are important factors of landscape dynamics in extent Arctic lowlands. Monitoring of spatial and temporal dynamics of such lakes will allow an assessment of permafrost stability and enhance the capabilities for modelling and quantifying biogeochemical processes related to permafrost degradation in a warming Arctic. In this study we use high-resolution remote sensing and GIS to analyze the development of thermokarst lakes and ponds in two study regions in North Siberia and Northwest Alaska. The sites are 1) the Cherskii region in the Kolyma lowland (Siberia) and 2) the Kitluk River area on the northern Seward Peninsula (Alaska). Both regions are characterized by continuous permafrost, a highly dissected and dynamic thermokarst landscape, uplands of Late Pleistocene permafrost deposits with high excess ice contents, and a large total volume of permafrost-stored carbon. These ice-rich Yedoma or Yedoma-like deposits are highly vulnerable to permafrost degradation forced by climate warming or other surface disturbance. Time series of high- resolution imagery (aerial, Corona, Ikonos, Alos Prism) covering more than 50 years of lake dynamics allow detailed assessments of processes and spatial patterns of thermokarst lake expansion and drainage in continuous permafrost. Time series of high-resolution imagery (aerial, Corona, Ikonos, Alos Prism) covering more than 50 years of lake dynamics allow detailed assessments of processes and spatial patterns of thermokarst lake expansion and drainage in continuous permafrost. Processes identified include thaw slumping, wave undercutting of frozen sediments or peat blocks and subsequent mass wasting, thaw collapse of near-shore zones, sinkhole formation and ice-wedge tunnelling, and gully formation by thermo-erosion. We use GIS-based tools to relate the remote sensing results to field data (ground ice content, topography, lithology, and relative age

  10. Evaluation of Mariut Lake water quality using Hyperspectral Remote Sensing and laboratory works

    Directory of Open Access Journals (Sweden)

    Neven G. Rostom

    2017-04-01

    The main objectives of this research are assessing water contamination by heavy metal in Mariut Lake using laboratory analysis and developing a predictive model for water pollution based on the spectral characteristics and lab data obtained. It is resulted that Pb, Ni and Cr concentrations exceed permissible limit of USEPA. Also, the spectral reflectance of (6–13, 16, 19 and 20 at wavelength 582–653 nm is related to the spectral behavior of the high chlorophyll concentration. Also there are 7 samples (1, 3, 6, 10, 11, 19 and 21 showed high and low values of turbidity. As the suspended sediment concentration increased, reflectance also increased at all wavelengths between 400 and 850 nm. It is concluded that most of models predicting heavy metals concentration using reflectance spectroscopy have high significant correlation ranged from 0.27 to 0.97.

  11. Coupling the WRF model with a temperature index model based on remote sensing for snowmelt simulations in a river basin in the Altay Mountains, northwest China

    Science.gov (United States)

    Wu, X.; Shen, Y.; Wang, N.; Pan, X.; Zhang, W.; He, J.; Wang, G.

    2017-12-01

    Snowmelt water is an important freshwater resource in the Altay Mountains in northwest China, and it is also crucial for local ecological system, economic and social sustainable development; however, warming climate and rapid spring snowmelt can cause floods that endanger both eco-environment and public and personal property and safety. This study simulates snowmelt in the Kayiertesi River catchment using a temperature-index model based on remote sensing coupled with high-resolution meteorological data obtained from NCEP reanalysis fields that were downscaled using Weather Research Forecasting model, then bias-corrected using a statistical downscaled model. Validation of the forcing data revealed that the high-resolution meteorological fields derived from downscaled NCEP reanalysis were reliable for driving the snowmelt model. Parameters of temperature-index model based on remote sensing were calibrated for spring 2014, and model performance was validated using MODIS snow cover and snow observations from spring 2012. The results show that the temperature-index model based on remote sensing performed well, with a simulation mean relative error of 6.7% and a Nash-Sutchliffe efficiency of 0.98 in spring 2012 in the river of Altay Mountains. Based on the reliable distributed snow water equivalent simulation, daily snowmelt runoff was calculated for spring 2012 in the basin. In the study catchment, spring snowmelt runoff accounts for 72% of spring runoff and 21% of annual runoff. Snowmelt is the main source of runoff for the catchment and should be managed and utilized effectively. The results provide a basis for snowmelt runoff predictions, so as to prevent snowmelt-induced floods, and also provide a generalizable approach that can be applied to other remote locations where high-density, long-term observational data is lacking.

  12. Remote Estimation of Chlorophyll-a in Inland Waters by a NIR-Red-Based Algorithm: Validation in Asian Lakes

    Directory of Open Access Journals (Sweden)

    Gongliang Yu

    2014-04-01

    Full Text Available Satellite remote sensing is a highly useful tool for monitoring chlorophyll-a concentration (Chl-a in water bodies. Remote sensing algorithms based on near-infrared-red (NIR-red wavelengths have demonstrated great potential for retrieving Chl-a in inland waters. This study tested the performance of a recently developed NIR-red based algorithm, SAMO-LUT (Semi-Analytical Model Optimizing and Look-Up Tables, using an extensive dataset collected from five Asian lakes. Results demonstrated that Chl-a retrieved by the SAMO-LUT algorithm was strongly correlated with measured Chl-a (R2 = 0.94, and the root-mean-square error (RMSE and normalized root-mean-square error (NRMS were 8.9 mg∙m−3 and 72.6%, respectively. However, the SAMO-LUT algorithm yielded large errors for sites where Chl-a was less than 10 mg∙m−3 (RMSE = 1.8 mg∙m−3 and NRMS = 217.9%. This was because differences in water-leaving radiances at the NIR-red wavelengths (i.e., 665 nm, 705 nm and 754 nm used in the SAMO-LUT were too small due to low concentrations of water constituents. Using a blue-green algorithm (OC4E instead of the SAMO-LUT for the waters with low constituent concentrations would have reduced the RMSE and NRMS to 1.0 mg∙m−3 and 16.0%, respectively. This indicates (1 the NIR-red algorithm does not work well when water constituent concentrations are relatively low; (2 different algorithms should be used in light of water constituent concentration; and thus (3 it is necessary to develop a classification method for selecting the appropriate algorithm.

  13. Monitoring and Attributions of Recent Dynamics in East Asia's Largest Fluvial Lake System: Integration of Remote Sensing, Hydrological Modeling, and Gauging Measurements

    Science.gov (United States)

    Wang, J.; Sheng, Y.; Wada, Y.

    2017-12-01

    The fluvial lake system across China's Yangtze Plain (YP), a World Wildlife Fund (WWF) ecoregion, are critical freshwater storages for nearly half a billion people. Our mapping using daily MODIS imagery revealed an approximately 10% net loss in the YP lake area from 2000 to 2011. Causes of this decadal lake decline were highly contentious, as it coincided with several meteorological droughts, a rising human water consumption (HWC), and the initial and yearly intensified water regulation from the world's largest hydroelectric project, the Three Gorges Dam (TGD). Here we integrated optical remote sensing, hydrological modeling, and in situ measurements to decouple the impacts of climate variability and anthropogenic activities including (i) Yangtze flow and sediment alterations by the TGD and (ii) HWC in agricultural, industrial, and domestic sectors throughout the downstream Yangtze Basin. Results suggest that this decadal lake decline was predominantly driven by climate variability closely linked to the El Niño-Southern Oscillation. Studied human activities, despite varying seasonal impacts that peak in fall, contribute ˜10-20% or less to the inter-annual lake area decline. Given that the TGD impacts on the total YP lake area and its seasonal variation are both under ˜5%, we also dismiss the speculation that the TGD might be responsible for evident downstream climate change by altering lake surface extent and thus open water evaporation. Nevertheless, anthropogenic impacts exhibited a strengthening trend during the past decade. Although the TGD has reached its full-capacity water regulation, the negative impacts of HWC and TGD-induced net channel erosion, which are already comparable to that of TGD's flow regulation, may continue to grow as crucial anthropogenic factors to future YP lake conservation.

  14. AL:PE Acidification of mountain lakes: Palaeolimnology and Ecology. Part 2. - Extention. Final report to the Norwegian Research Council; AL:PE Acidification of mountain lakes: palaeolimnology and ecology. Part 2 - Utvidelse. Sluttrapport til Norges forskningsraad

    Energy Technology Data Exchange (ETDEWEB)

    Wathne, B M; Rosseland, B O; Lien, L

    1996-09-01

    Alpine and arctic regions, the least affected areas of Europe, are threatened by acid precipitation and long-range pollution. The international project discussed in this report was started to assess the conditions for alpine or arctic lakes, chemically and biologically combined with analyses of sediment cores. The work was done on lakes of various degrees of acidification and the results may be used to evaluate how fast the environment is changing, in what direction, and biological effects. The AL:PE project is the first comprehensive study of alpine lakes on a European level. The project was financed through EU`s research programme combined with funds from the participating countries. The project, which is now finally ending after 5 years of activity, is briefly surveyed in the report. One of the conclusions is that contamination from long-range pollutants can be found in even the most outlying places. 58 refs., 106 figs., 58 tabs.

  15. The potential of remote sensing for monitoring land cover changes and effects on physical geography in the area of Kayisdagi Mountain and its surroundings (Istanbul).

    Science.gov (United States)

    Geymen, Abdurrahman; Baz, Ibrahim

    2008-05-01

    The effect of land cover change, from natural to anthropogenic, on physical geography conditions has been studied in Kayisdagi Mountain. Land degradation is the most important environmental issue involved in this study. Most forms of land degradation are natural processes accelerated by human activity. Land degradation is a human induced or natural process that negatively affects the ability of land to function effectively within an ecosystem. Environmental degradation from human pressure and land use has become a major problem in the study area because of high population growth, urbanization rate, and the associated rapid depletion of natural resources. When studying the cost of land degradation, it is not possible to ignore the role of urbanization. In particular, a major cause of deforestation is conversion to urban land. The paper reviews the principles of current remote sensing techniques considered particularly suitable for monitoring Kayisdagi Mountain and its surrounding land cover changes and their effects on physical geography conditions. In addition, this paper addresses the problem of how spatially explicit information about degradation processes in the study area rangelands can be derived from different time series of satellite data. The monitoring approach comprises the time period between 1990 and 2005. Satellite remote sensing techniques have proven to be cost effective in widespread land cover changes. Physical geography and particularly natural geomorphologic processes like erosion, mass movement, physical weathering, and chemical weathering features etc. have faced significant unnatural variation.

  16. Detecting Mountain Peaks and Delineating Their Shapes Using Digital Elevation Models, Remote Sensing and Geographic Information Systems Using Autometric Methodological Procedures

    Directory of Open Access Journals (Sweden)

    Tomaž Podobnikar

    2012-03-01

    Full Text Available The detection of peaks (summits as the upper parts of mountains and the delineation of their shape is commonly confirmed by inspections carried out by mountaineers. In this study the complex task of peak detection and shape delineation is solved by autometric methodological procedures, more precisely, by developing relatively simple but innovative image-processing and spatial-analysis techniques (e.g., developing inventive variables using an annular moving window in remote sensing and GIS domains. The techniques have been integrated into automated morphometric methodological procedures. The concepts of peaks and their shapes (sharp, blunt, oblong, circular and conical were parameterized based on topographic and morphologic criteria. A geomorphologically high quality DEM was used as a fundamental dataset. The results, detected peaks with delineated shapes, have been integratively enriched with numerous independent datasets (e.g., with triangulated spot heights and information (e.g., etymological information, and mountaineering criteria have been implemented to improve the judgments. This holistic approach has proved the applicability of both highly standardized and universal parameters for the geomorphologically diverse Kamnik Alps case study area. Possible applications of this research are numerous, e.g., a comprehensive quality control of DEM or significantly improved models for the spatial planning proposes.

  17. Zooplankton community composition of high mountain lakes in the Tatra Mts., the Alps in North Tyrol, and Scotland: relationship to pH, depth, organic carbon, and chlorophyll-a concentration

    Directory of Open Access Journals (Sweden)

    Skála Ivan

    2015-10-01

    Full Text Available The European EMERGE (European Mountain lake Ecosystems: Regionalisation, diaGnostic & socio-economic Evaluation project was a survey of high mountain lakes (above treeline across Europe using unified methods of sampling and analysis. The sampling was carried out in summer or autumn 2000, and comprised biological samples, and samples for chemical analysis. Data from three lake districts are used in this paper: the Tatra Mts. in Slovakia and Poland (45 lakes, the Alps in Tyrol in Austria (22 lakes, and Scotland (30 lakes. As it is shown by multiple regression analysis, DTOC (dissolved or total organic carbon is the key variable for most groups of zooplankton. With increasing DTOC and mostly with chlorophyll-a decreasing, pH increasing and depth decreasing, macrofitrators with coarse filter meshes are replaced by microfiltrators with fine filter meshes. Higher DTOC may increase bacterioplankton production and advantage species able to consume bacteria (microfiltrators. Other zooplankton species also differ in their preference for DTOC, chlorophyll-a, pH and depth, but DTOC being positively correlated with chlorophyll-a and pH positively correlated with depth. It may be caused by their different preference for food quality in terms of C:P ratio.

  18. Role of Climate Variability and Human Activity on Poopó Lake Droughts between 1990 and 2015 Assessed Using Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Frédéric Satgé

    2017-02-01

    Full Text Available In 2015, an emergency state was declared in Bolivia when Poopó Lake dried up. Climate variability and the increasing need for water are potential factors responsible for this situation. Because field data are missing over the region, no statements are possible about the influence of mentioned factors. This study is a preliminary step toward the understanding of Poopó Lake drought using remote sensing data. First, atmospheric corrections for Landsat (FLAASH and L8SR, seven satellite derived indexes for extracting water bodies, MOD16 evapotranspiration, PERSIANN-CDR and MSWEP rainfall products potentiality were assessed. Then, the fluctuations of Poopó Lake extent over the last 26 years are presented for the first time jointly, with the mean regional annual rainfall. Three main droughts are highlighted between 1990 and 2015: two are associated with negative annual rainfall anomalies in 1994 and 1995 and one associated with positive annual rainfall anomaly in 2015. This suggests that other factors than rainfall influenced the recent disappearance of the lake. The regional evapotranspiration increased by 12.8% between 2000 and 2014. Evapotranspiration increase is not homogeneous over the watershed but limited over the main agriculture regions. Agriculture activity is one of the major factors contributing to the regional desertification and recent disappearance of Poopó Lake.

  19. Monitoring Hydrological Patterns of Temporary Lakes Using Remote Sensing and Machine Learning Models: Case Study of La Mancha Húmeda Biosphere Reserve in Central Spain

    Directory of Open Access Journals (Sweden)

    Carolina Doña

    2016-07-01

    Full Text Available The Biosphere Reserve of La Mancha Húmeda is a wetland-rich area located in central Spain. This reserve comprises a set of temporary lakes, often saline, where water level fluctuates seasonally. Water inflows come mainly from direct precipitation and runoff of small lake watersheds. Most of these lakes lack surface outlets and behave as endorheic systems, where water withdrawal is mainly due to evaporation, causing salt accumulation in the lake beds. Remote sensing was used to estimate the temporal variation of the flooded area in these lakes and their associated hydrological patterns related to the seasonality of precipitation and evapotranspiration. Landsat 7 ETM+ satellite images for the reference period 2013–2015 were jointly used with ground-truth datasets. Several inverse modeling methods, such as two-band and multispectral indices, single-band threshold, classification methods, artificial neural network, support vector machine and genetic programming, were applied to retrieve information on the variation of the flooded areas. Results were compared to ground-truth data, and the classification errors were evaluated by means of the kappa coefficient. Comparative analyses demonstrated that the genetic programming approach yielded the best results, with a kappa value of 0.98 and a total error of omission-commission of 2%. The dependence of the variations in the water-covered area on precipitation and evaporation was also investigated. The results show the potential of the tested techniques to monitor the hydrological patterns of temporary lakes in semiarid areas, which might be useful for management strategy-linked lake conservation and specifically to accomplish the goals of both the European Water Framework Directive and the Habitats Directive.

  20. Geologic remote sensing study of the Hayden pass-Orient Mine Area, Northern Sangre de Cristo Mountains, Colorado

    Science.gov (United States)

    Wychgram, D. C.

    1972-01-01

    Remote sensor data from a NASA Convair 990 radar flight and Mission 101 and 105 have been interpreted and evaluated. Based on interpretation of the remote sensor data, a geologic map has been prepared and compared with a second geologic map, prepared from interpretation of both remote sensor data and field data. Comparison of the two maps gives one indication of the usefulness and reliability of the remote sensor data. Color and color infrared photography provided the largest amount of valuable information. Multiband photography was of lesser value and side-looking radar imagery provided no new information that was not available on small scale photography. Thermal scanner imagery proved to be a very specialized remote sensing tool that should be applied to areas of low relief and sparse vegetation where geologic features produce known or suspected thermal contrast. Low sun angle photography may be a good alternative to side-looking radar imagery but must be flown with critical timing.

  1. Integrating remote sensing approach with pollution monitoring tools for aquatic ecosystem risk assessment and management: a case study of Lake Victoria (Uganda).

    Science.gov (United States)

    Focardi, Silvia; Corsi, Ilaria; Mazzuoli, Stefania; Vignoli, Leonardo; Loiselle, Steven A; Focardi, Silvano

    2006-11-01

    Aquatic ecosystems around the world, lake, estuaries and coastal areas are increasingly impacted by anthropogenic pollutants through different sources such as agricultural, industrial and urban discharges, atmospheric deposition and terrestrial drainage. Lake Victoria is the second largest lake in the world and the largest tropical lake. Bordered by Tanzania, Uganda, and Kenya, it provides a livelihood for millions of Africans in the region. However, the lake is under threat from eutrophication, a huge decline in the number of native fish species caused by several factors including loss of biodiversity, over fishing and pollution has been recently documented. Increasing usage of pesticides and insecticides in the adjacent agricultural areas as well as mercury contamination from processing of gold ore on the southern shores are currently considered among the most emergent phenomena of chemical contamination in the lake. By the application of globally consistent and comprehensive geospatial data-sets based on remote sensing integrated with information on heavy metals accumulation and insecticides exposure in native and alien fish populations, the present study aims at assessing the environmental risk associated to the contamination of the Lake Victoria water body on fish health, land cover distribution, biodiversity and the agricultural area surrounding the lake. By the elaboration of Landsat 7 TM data of November 2002 and Landsat 7 TM 1986 we have calculated the agriculture area which borders the Lake Victoria bay, which is an upland plain. The resulting enhanced nutrient loading to the soil is subsequently transported to the lake by rain or as dry fall. The data has been inserted in a Geographical information System (ARCGIS) to be upgraded and consulted. Heavy metals in fish fillets showed concentrations rather low except for mercury being higher than others as already described in previous investigations. In the same tissue, cholinesterases activity (ChE) as an

  2. Analysis of Influential Factors Associated with the Smoking Behavior of Aboriginal Schoolchildren in Remote Taiwanese Mountainous Areas

    Science.gov (United States)

    Huang, Hsiao-Ling; Hsu, Chih-Cheng; Peng, Wu-Der; Yen, Yea-Yin; Chen, Ted; Hu, Chih-Yang; Shi, Hon-Yi; Lee, Chien-Hung; Chen, Fu-Li; Lin, Pi-Li

    2012-01-01

    Background: A disparity in smoking behavior exists between the general and minority populations residing in Taiwan's mountainous areas. This study analyzed individual and environmental factors associated with children's smoking behavior in these areas of Taiwan. Methods: In this school-based study, data on smoking behavior and related factors for…

  3. Detection and mapping of mountain pine beetle red attack: Matching information needs with appropriate remotely sensed data

    Science.gov (United States)

    M. A. Wulder; J. C. White; B. J. Bentz

    2005-01-01

    Estimates of the location and extent of the red attack stage of mountain pine beetle (Dentroctonus ponderosae Hopkins) infestations are critical for forest management. The degree of spatial and temporal precision required for these estimates varies according to the management objectives and the nature of the infestation. This paper outlines a hierarchy of information...

  4. Source-receptor relationships for speciated atmospheric mercury at the remote Experimental Lakes Area, northwestern Ontario, Canada

    Directory of Open Access Journals (Sweden)

    I. Cheng

    2012-02-01

    Full Text Available Source-receptor relationships for speciated atmospheric mercury measured at the Experimental Lakes Area (ELA, northwestern Ontario, Canada were investigated using various receptor-based approaches. The data used in this study include gaseous elemental mercury (GEM, mercury bound to fine airborne particles (<2.5 μm (PHg, reactive gaseous mercury (RGM, major inorganic ions, sulphur dioxide, nitric acid gas, ozone, and meteorological variables, all of which were measured between May 2005 and December 2006. The source origins identified were related to transport of industrial and combustion emissions (associated with elevated GEM, photochemical production of RGM (associated with elevated RGM, road-salt particles with absorption of gaseous Hg (associated with elevated PHg and RGM, crustal/soil emissions, and background pollution. Back trajectory modelling illustrated that a remote site, like ELA, is affected by distant Hg point sources in Canada and the United States. The sources identified from correlation analysis, principal components analysis and K-means cluster analysis were generally consistent. The discrepancies between the K-means and Hierarchical cluster analysis were the clusters related to transport of industrial/combustion emissions, photochemical production of RGM, and crustal/soil emissions. Although it was possible to assign the clusters to these source origins, the trajectory plots for the Hierarchical clusters were similar to some of the trajectories belonging to several K-means clusters. This likely occurred because the variables indicative of transport of industrial/combustion emissions were elevated in at least two or more of the clusters, which means this Hg source was well-represented in the data.

  5. Remote sensing appraisal of Lake Chad shrinkage connotes severe impacts on green economics and socio-economics of the catchment area.

    Science.gov (United States)

    Onamuti, Olapeju Y; Okogbue, Emmanuel C; Orimoloye, Israel R

    2017-11-01

    Lake Chad commonly serves as a major hub of fertile economic activities for the border communities and contributes immensely to the national growth of all the countries that form its boundaries. However, incessant and multi-decadal drying via climate change pose greater threats to this transnational water resource, and adverse effects on ecological sustainability and socio-economic status of the catchment area. Therefore, this study assessed the extent of shrinkage of Lake Chad using remote sensing. Landsat imageries of the lake and its surroundings between 1987 and 2005 were retrieved from Global Land Cover Facility website and analysed using Integrated Land and Water Information System version 3.3 (ILWIS 3.3). Supervised classification of area around the lake was performed into various land use/land cover classes, and the shrunk part of its environs was assessed based on the land cover changes. The shrinkage trend within the study period was also analysed. The lake water size reduced from 1339.018 to 130.686 km 2 (4.08-3.39%) in 1987-2005. The supervised classification of the Landsat imageries revealed an increase in portion of the lake covered by bare ground and sandy soil within the reference years (13 490.8-17 503.10 km 2 ) with 4.98% total range of increase. The lake portion intersected with vegetated ground and soil also reduced within the period (11 046.44-10 078.82 km 2 ) with 5.40% (967.62 km 2 ) total decrease. The shrunk part of the lake covered singly with vegetation increased by 2.74% from 1987 to 2005. The shrunk part of the lake reduced to sand and turbid water showed 5.62% total decrease from 1987 to 2005 and a total decrease of 1805.942 km 2 in area. The study disclosed an appalling rate of shrinkage and damaging influences on the hydrologic potential, eco-sustainability and socio-economics of the drainage area as revealed using ILWIS 3.3.

  6. Deriving a time series of 3D glacier motion to investigate interactions of a large mountain glacial system with its glacial lake: Use of Synthetic Aperture Radar Pixel Offset-Small Baseline Subset technique

    Science.gov (United States)

    Li, Jia; Li, Zhi-wei; Wu, Li-xin; Xu, Bing; Hu, Jun; Zhou, Yu-shan; Miao, Ze-lang

    2018-04-01

    We investigated the interactions of Lake Merzbacher with the Southern Inylchek Glacier (Central Tien Shan) using the Synthetic Aperture Radar (SAR) Pixel Offset-Small Baseline Subset (PO-SBAS) to derive a time series of three-dimensional (3D) glacier motion. The measurements of 3D glacier velocity were ∼17% more precise than a previous study that did not use the SBAS estimation. The velocities of the glacier were up to 58 cm/day east, 70 cm/day north, and 113 cm/day vertically. Combining these data with Landsat images indicated that movement of the glacier is sensitive to changes of Lake Merzbacher. Specifically, the entry of more lake water into the glacier during the ablation season increased englacial ablation due to thermal erosion. Moreover, ice calving begins when the lake water gradually lifts the ice dam. Calving can cause greater loss of glacier mass than normal ablation. Trying to replenish the front mass loss, the distributary accelerates and the mass loss further intensifies. A time series of the vertical velocity indicates that the glacier tongue has a huge englacial cavity. We suggest that the lake outburst is directly related to the crack of this cavity. Bursting of the lake triggers a mini-surge at the glacier tongue. The vertical velocity at the ice dam was ∼+60 cm/day before the lake outburst, and ∼-113 cm/day afterwards. After drainage of the lake, flow velocities at the distributary, do not sharply decrease because pre-drainage mass loss needs to be replenished by fast flow. Based on comparisons with previous measurements, our results indicate that the lake had an increasing influence on the glacier from 2005 to 2009. This study demonstrates that a time series of 3D glacier motion based on the PO-SBAS technique is effective for assessing the dynamics of a mountain glacial system and interactions with its glacial lake.

  7. Childbirth traditions and cultural perceptions of safety in Nepal: critical spaces to ensure the survival of mothers and newborns in remote mountain villages.

    Science.gov (United States)

    Kaphle, Sabitra; Hancock, Heather; Newman, Lareen A

    2013-10-01

    to uncover local beliefs regarding pregnancy and birth in remote mountainous villages of Nepal in order to understand the factors which impact on women's experiences of pregnancy and childbirth and the related interplay of tradition, spiritual beliefs, risk and safety which impact on those experiences. this study used a qualitative methodological approach with in-depth interviews framework within social constructionist and feminist critical theories. the setting comprised two remote Nepalese mountain villages where women have high rates of illiteracy, poverty, disadvantage, maternal and newborn mortality, and low life expectancy. Interviews were conducted between February and June, 2010. twenty five pregnant/postnatal women, five husbands, five mothers-in-law, one father-in-law, five service providers and five community stakeholders from the local communities were involved. Nepalese women, their families and most of their community strongly value their childbirth traditions and associated spiritual beliefs and they profoundly shape women's views of safety and risk during pregnancy and childbirth, influencing how birth and new motherhood fit into daily life. These intense culturally-based views of childbirth safety and risk conflict starkly with the medical view of childbirth safety and risk. if maternity services are to improve maternal and neonatal survival rates in Nepal, maternity care providers must genuinely partner with local women inclusive of their cultural beliefs, and provide locally based primary maternity care. Women will then be more likely to attend maternity care services, and benefit from feeling culturally safe and culturally respected within their spiritual traditions of birth supported by the reduction of risk provided by informed and reverent medicalised care. © 2013 Elsevier Ltd. All rights reserved.

  8. Quantification of spatial temporal variability of snow cover and hydro-climatic variables based on multi-source remote sensing data in the Swat watershed, Hindukush Mountains, Pakistan

    Science.gov (United States)

    Anjum, Muhammad Naveed; Ding, Yongjian; Shangguan, Donghui; Liu, Junguo; Ahmad, Ijaz; Ijaz, Muhammad Wajid; Khan, Muhammad Imran

    2018-02-01

    The northern part of Hindukush Mountains has a perplexing environment due to the influence of adjacent mountains of Himalaya, Karakoram, and Tibetan Plateau. Although reliable evidences of climate change are available; however, a clear knowledge of snow cover dynamics in the context of climate change is missing for this region. In this study, we used various remotely sensed (TRMM precipitation product, while MODIS temperature and snow cover products) and gauge-based datasets to quantify the spatiotemporal variability of climatic variables and their turn effects over the snow cover area (SCA) and river discharge in the Swat watershed, northern Hindukush Mountains, Pakistan. The Mann-Kendall method and Sen's slope estimator were used to estimate the trends in SCA and hydro-climatic variables, at 5% significant level (P = 0.05). Results show that the winter and springs temperatures have increased (at the rate of 0.079 and 0.059 °C year-1, respectively), while decreasing in the summer and autumn (at the rate of 0.049 and 0.070 °C year-1, respectively). Basin-wide increasing tendency of precipitation was identified with a highest increasing rate of 3.563 mm year-1 in the spring season. A decreasing trend in the winter SCA (at the rate of -0.275% year-1) and increasing trends in other seasons were identified. An increasing tendency of river discharge on annual and seasonal scales was also witnessed. The seasonal variations in discharge showed significant positive and negative relationships with temperature and SCA, respectively. We conclude that the future variations in the temperature and SCA in the higher altitudes of the Swat watershed could substantially affect the seasonality of the river discharge. Moreover, it implies that the effect of ongoing global warming on the SCA in the snowmelt-dominated river basins needs to be considered for sustainable regional planning and management of water resources, hydropower production, and downstream irrigation scheduling.

  9. Identification of glacier motion and potentially dangerous glacial lakes in the Mt. Everest region/Nepal using spaceborne imagery

    Directory of Open Access Journals (Sweden)

    T. Bolch

    2008-12-01

    Full Text Available Failures of glacial lake dams can cause outburst floods and represents a serious hazard. The potential danger of outburst floods depends on various factors like the lake's area and volume, glacier change, morphometry of the glacier and its surrounding moraines and valley, and glacier velocity. Remote sensing offers an efficient tool for displacement calculations and risk assessment of the identification of potentially dangerous glacial lakes (PDGLs and is especially helpful for remote mountainous areas. Not all important parameters can, however, be obtained using spaceborne imagery. Additional interpretation by an expert is required. ASTER data has a suitable accuracy to calculate surface velocity. Ikonos data offers more detail but requires more effort for rectification. All investigated debris-covered glacier tongues show areas with no or very slow movement rates. From 1962 to 2003 the number and area of glacial lakes increased, dominated by the occurrence and almost linear areal expansion of the moraine-dammed lakes, like the Imja Lake. Although the Imja Lake will probably still grow in the near future, the risk of an outburst flood (GLOF is considered not higher than for other glacial lakes in the area. Potentially dangerous lakes and areas of lake development are identified. There is a high probability of further lake development at Khumbu Glacier, but a low one at Lhotse Glacier.

  10. Studies on mountain streams in the English lake district III. Aspects of water chemistry in Brownrigg Well, Whelpside Ghyll

    Energy Technology Data Exchange (ETDEWEB)

    Sutcliffe, D W; Carrick, T R

    1973-01-01

    Comparisons are made of pH and the concentrations of major ions in streamwater from Brownrigg Well (the source of Whelpside Ghyll) and from the River Duddon. PH in Brownrigg Well is usually >5.7, but the concentrations of sodium, potassium and possibly calcium are near to the minima required to support the amphipod Gammarus pulex. In contrast most insect taxa are not affected by low ionic concentrations. It is postulated that these had a wider distribution in mountain streams prior to the acidification of poorly buffered waters by acid rainfall resulting from large-scale combustion of fossil fuels.

  11. Thermal remote sensing of water under flooded vegetation: New observations of inundation patterns for the ‘Small’ Lake Chad

    Science.gov (United States)

    Leblanc, M.; Lemoalle, J.; Bader, J.-C.; Tweed, S.; Mofor, L.

    2011-06-01

    SummaryLake Chad at the border of the Sahara desert in central Africa, is well known for its high sensitivity to hydroclimatic events. Gaps in in situ data have so far prevented a full assessment of the response of Lake Chad to the ongoing prolonged drought that started in the second half of the 20th century. Like many other wetlands and shallow lakes, the 'Small' Lake Chad includes large areas of water under aquatic vegetation which needs to be accounted for to obtain the total inundated area. In this paper, a methodology is proposed that uses Meteosat thermal maximum composite data (Tmax) to account for water covered by aquatic vegetation and provide a consistent monthly time series of total inundated area estimates for Lake Chad. Total inundation patterns in Lake Chad were reconstructed for a 15-yr period (1986-2001) which includes the peak of the drought (86-91) and therefore provides new observations on the hydrological functioning of the 'Small' Lake Chad. During the study period, Lake Chad remained below 16,400 km 2 (third quartile ˜8800 km 2). The variability of the inundated area observed in the northern pool (standard deviation σnorthern pool = 1980 km 2) is about 60% greater than that of the southern pool ( σsouthern pool = 1250 km 2). The same methodology could be applied to other large wetlands and shallow lakes in semi-arid or arid regions elsewehere using Meteosat (e.g. Niger Inland Delta, Sudd in Sudan, Okavango Delta) and other weather satellites (e.g., floodplains of the Lake Eyre Basin in Australia and Andean Altiplano Lakes in South America).

  12. Multi-Spectral Remote Sensing of Phytoplankton Pigment Absorption Properties in Cyanobacteria Bloom Waters: A Regional Example in the Western Basin of Lake Erie

    Directory of Open Access Journals (Sweden)

    Guoqing Wang

    2017-12-01

    Full Text Available Phytoplankton pigments absorb sunlight for photosynthesis, protect the chloroplast from damage caused by excess light energy, and influence the color of the water. Some pigments act as bio-markers and are important for separation of phytoplankton functional types. Among many efforts that have been made to obtain information on phytoplankton pigments from bio-optical properties, Gaussian curves decomposed from phytoplankton absorption spectrum have been used to represent the light absorption of different pigments. We incorporated the Gaussian scheme into a semi-analytical model and obtained the Gaussian curves from remote sensing reflectance. In this study, a series of sensitivity tests were conducted to explore the potential of obtaining the Gaussian curves from multi-spectral satellite remote sensing. Results showed that the Gaussian curves can be retrieved with 35% or less mean unbiased absolute percentage differences from MEdium Resolution Imaging Spectrometer (MERIS and Moderate Resolution Imaging Spectroradiometer (MODIS-like sensors. Further, using Lake Erie as an example, the spatial distribution of chlorophyll a and phycocyanin concentrations were obtained from the Gaussian curves and used as metrics for the spatial extent of an intense cyanobacterial bloom occurred in Lake Erie in 2014. The seasonal variations of Gaussian absorption properties in 2011 were further obtained from MERIS imagery. This study shows that it is feasible to obtain Gaussian curves from multi-spectral satellite remote sensing data, and the obtained chlorophyll a and phycocyanin concentrations from these Gaussian peak heights demonstrated potential application to monitor harmful algal blooms (HABs and identification of phytoplankton groups from satellite ocean color remote sensing semi-analytically.

  13. Remote sensing of aquatic vegetation distribution in Taihu Lake using an improved classification tree with modified thresholds.

    Science.gov (United States)

    Zhao, Dehua; Jiang, Hao; Yang, Tangwu; Cai, Ying; Xu, Delin; An, Shuqing

    2012-03-01

    Classification trees (CT) have been used successfully in the past to classify aquatic vegetation from spectral indices (SI) obtained from remotely-sensed images. However, applying CT models developed for certain image dates to other time periods within the same year or among different years can reduce the classification accuracy. In this study, we developed CT models with modified thresholds using extreme SI values (CT(m)) to improve the stability of the models when applying them to different time periods. A total of 903 ground-truth samples were obtained in September of 2009 and 2010 and classified as emergent, floating-leaf, or submerged vegetation or other cover types. Classification trees were developed for 2009 (Model-09) and 2010 (Model-10) using field samples and a combination of two images from winter and summer. Overall accuracies of these models were 92.8% and 94.9%, respectively, which confirmed the ability of CT analysis to map aquatic vegetation in Taihu Lake. However, Model-10 had only 58.9-71.6% classification accuracy and 31.1-58.3% agreement (i.e., pixels classified the same in the two maps) for aquatic vegetation when it was applied to image pairs from both a different time period in 2010 and a similar time period in 2009. We developed a method to estimate the effects of extrinsic (EF) and intrinsic (IF) factors on model uncertainty using Modis images. Results indicated that 71.1% of the instability in classification between time periods was due to EF, which might include changes in atmospheric conditions, sun-view angle and water quality. The remainder was due to IF, such as phenological and growth status differences between time periods. The modified version of Model-10 (i.e. CT(m)) performed better than traditional CT with different image dates. When applied to 2009 images, the CT(m) version of Model-10 had very similar thresholds and performance as Model-09, with overall accuracies of 92.8% and 90.5% for Model-09 and the CT(m) version of Model

  14. Using high-resolution in situ radon measurements to determine groundwater discharge at a remote location: Tonle Sap Lake, Cambodia

    International Nuclear Information System (INIS)

    Burnett, W.C.; Chanyotha, S.

    2013-01-01

    Tonle Sap Lake (Cambodia) is the largest freshwater lake in SE Asia, and is reported to have one of the highest freshwater fish productions anywhere. During the dry season (November-April) the lake drains through a tributary to the Mekong River. The flow in the connecting tributary completely reverses during the wet monsoon (May-October), adding huge volumes of water back to the lake, increasing its area about fourfold. We hypothesize that nutrients are at least partially delivered via groundwater discharge, especially during the draining portion of the annual flood cycle. We surveyed over 200 km in the northern section of the lake using a customized system that measures natural 222 Rn (radon), temperature, conductivity, GPS coordinates and water depth while underway. Results showed that there were portions of the lake with significant enrichments in radon, indicating likely groundwater inputs. These same areas were generally characterized by lower electrical conductivities. Samples collected from nearby wells also showed a general inverse relationship between radon and conductivity. Our data suggest that groundwater pathways are important, accounting for roughly 10-20 % of the freshwater flow of the Tonle Sap tributary (connection to the Mekong River), the largest single source of fresh water to the lake. Nutrient inputs from these inputs, because of higher concentrations in groundwater, will be correspondingly higher. (author)

  15. Turbidity retrieval and monitoring of Danube Delta waters using multi-sensor optical remote sensing data: An integrated view from the delta plain lakes to the western-northwestern Black Sea coastal zone

    OpenAIRE

    Guttler, Fabio; Niculescu, Simona; Gohin, Francis

    2013-01-01

    Based on multi-sensor optical remote sensing techniques, more than 80 medium and high spatial resolution satellite images were used for studying the turbidity patterns of Danube Delta waters. During a selected 4-year temporal coverage (2006 to 2009), the turbidity gradients were simultaneously analyzed in the delta plain lakes and in the Black Sea western-northwestern coastal zone. Two distinct, but complementary, methodologies for retrieving turbidity were employed, one for the lakes and the...

  16. Subjective assessment of acute mountain sickness: investigating the relationship between the Lake Louise Self-Report, a visual analogue scale and psychological well-being scales.

    Science.gov (United States)

    Frühauf, Anika; Burtscher, Martin; Pocecco, Elena; Faulhaber, Martin; Kopp, Martin

    2016-01-01

    There is an ongoing discussion how to assess acute mountain sickness (AMS) in real life conditions. Next to more-item scales with a cut off like the Lake Louise Self-Report (LLS), some authors suggested to use visual analog scales (VAS) to assess AMS. This study tried to contribute to this question using VAS items used for the Subjective Ratings of Drug Effects, including an additional single item for AMS. Furthermore, we investigated if instruments developed to assess psychological well-being might predict AMS assessed via LLS or VAS. 32 (19 Female) adult persons with known AMS susceptibility filled in questionnaires (Feeling Scale, Felt Arousal Scale, Activation Deactivation Check List, LLS, VAS) at a height of 3650 m above sea level. Correlation and regression analysis suggest a moderate to high relationship between the LLS score and the VAS items, including one VAS item asking for the severity of AMS, as well as psychological well-being. In conclusion, using VAS items to assess AMS can be a more precise alternative to questionnaires like LLS, for people knowledgeable with AMS. Furthermore, researchers should be aware that psychological well-being might be an important parameter influencing the assessment of AMS.

  17. Supergene destruction of a hydrothermal replacement alunite deposit at Big Rock Candy Mountain, Utah: Mineralogy, spectroscopic remote sensing, stable-isotope, and argon-age evidences

    Science.gov (United States)

    Cunningham, Charles G.; Rye, Robert O.; Rockwell, Barnaby W.; Kunk, Michael J.; Councell, Terry B.

    2005-01-01

    Big Rock Candy Mountain is a prominent center of variegated altered volcanic rocks in west-central Utah. It consists of the eroded remnants of a hypogene alunite deposit that, at ∼21 Ma, replaced intermediate-composition lava flows. The alunite formed in steam-heated conditions above the upwelling limb of a convection cell that was one of at least six spaced at 3- to 4-km intervals around the margin of a monzonite stock. Big Rock Candy Mountain is horizontally zoned outward from an alunite core to respective kaolinite, dickite, and propylite envelopes. The altered rocks are also vertically zoned from a lower pyrite–propylite assemblage upward through assemblages successively dominated by hypogene alunite, jarosite, and hematite, to a flooded silica cap. This hydrothermal assemblage is undergoing natural destruction in a steep canyon downcut by the Sevier River in Marysvale Canyon. Integrated geological, mineralogical, spectroscopic remote sensing using AVIRIS data, Ar radiometric, and stable isotopic studies trace the hypogene origin and supergene destruction of the deposit and permit distinction of primary (hydrothermal) and secondary (weathering) processes. This destruction has led to the formation of widespread supergene gypsum in cross-cutting fractures and as surficial crusts, and to natrojarosite, that gives the mountain its buff coloration along ridges facing the canyon. A small spring, Lemonade Spring, with a pH of 2.6 and containing Ca, Mg, Si, Al, Fe, Mn, Cl, and SO4, also occurs near the bottom of the canyon. The 40Ar/39Ar age (21.32±0.07 Ma) of the alunite is similar to that for other replacement alunites at Marysvale. However, the age spectrum contains evidence of a 6.6-Ma thermal event that can be related to the tectonic activity responsible for the uplift that led to the downcutting of Big Rock Candy Mountain by the Sevier River. This ∼6.6 Ma event also is present in the age spectrum of supergene natrojarosite forming today, and probably

  18. Assessment and prediction of land ecological environment quality change based on remote sensing-a case study of the Dongting lake area in China

    Science.gov (United States)

    Hu, Wenmin; Wang, Zhongcheng; Li, Chunhua; Zhao, Jin; Li, Yi

    2018-02-01

    Multi-source remote sensing data is rarely used for the comprehensive assessment of land ecologic environment quality. In this study, a digital environmental model was proposed with the inversion algorithm of land and environmental factors based on the multi-source remote sensing data, and a comprehensive index (Ecoindex) was applied to reconstruct and predict the land environment quality of the Dongting Lake Area to assess the effect of human activities on the environment. The main finding was that with the decrease of Grade I and Grade II quality had a decreasing tendency in the lake area, mostly in suburbs and wetlands. Atmospheric water vapour, land use intensity, surface temperature, vegetation coverage, and soil water content were the main driving factors. The cause of degradation was the interference of multi-factor combinations, which led to positive and negative environmental agglomeration effects. Positive agglomeration, such as increased rainfall and vegetation coverage and reduced land use intensity, could increase environmental quality, while negative agglomeration resulted in the opposite. Therefore, reasonable ecological restoration measures should be beneficial to limit the negative effects and decreasing tendency, improve the land ecological environment quality and provide references for macroscopic planning by the government.

  19. Investigating changes in land use cover and associated environmental parameters in Taihu Lake in recent decades using remote sensing and geochemistry.

    Directory of Open Access Journals (Sweden)

    Changchun Huang

    Full Text Available Humans have had a significant impact on the terrestrial pedosphere through activities such as agriculture and urbanization. The effects of human activities on land use and the related environmental changes were investigated through point and areal studies surrounding Meiliang Bay, which is an open area of extreme eutrophication in Taihu Lake, China. This study used remote sensing and environmental-tracer profiles [total nitrogen (TN, total phosphorus (TP, total organic carbon (TOC, grain size, and geochemical parameters] to determine the causes of changes in land use and the associated environmental parameters. The results of LUCCs (Land use/cover changes indicate that over the past three decades, total farmland decreased by 862.49 km2, with an annual decrement rate of 28.75 km2/year, and total urbanized land increased by 859.71 km2, with an annual growth rate of 28.66 km2/year. The geochemical results indicate that the trophic state of Taihu Lake was persistently intensifying and that the TN, TP, and TOC concentrations increased twofold, threefold, and twofold, respectively, from 1949 to 2010. The sources of TN, TP, and TOC were highly similar after 1975. However, before 1974, TN and TP originated from different sources than TOC. The grassland and woodland around the lake retain nutrients and sand from the land of study area. The increase in urbanized land and tertiary industries significantly increased the sediment concentrations of TN, TP, and TOC after 1980.

  20. Analysis of Suspended Particulate Matter and Its Drivers in Sahelian Ponds and Lakes by Remote Sensing (Landsat and MODIS: Gourma Region, Mali

    Directory of Open Access Journals (Sweden)

    Elodie Robert

    2017-12-01

    Full Text Available The Sahelian region is characterized by significant variations in precipitation, impacting water quantity and quality. Suspended particulate matter (SPM dynamics has a significant impact on inland water ecology and water resource management. In-situ data in this region are scarce and, consequently, the environmental factors triggering SPM variability are yet to be understood. This study addresses these issues using remote sensing optical data. Turbidity and SPM of the Agoufou Lake in Sahelian Mali were measured from October 2014 to present, providing a large range of `values (SPM ranging from 106 to 4178 mg/L. These data are compared to satellite reflectance from Landsat (ETM+, OLI and MODIS (MOD09GQ, MYD09GQ. For each of these sensors, a spectral band in the near infrared region is found to be well suited to retrieve turbidity and SPM, up to very high values (R2 = 0.70 seldom addressed by remote sensing studies. The satellite estimates are then employed to assess the SPM dynamics in the main lakes and ponds of the Gourma region and its links to environmental and anthropogenic factors. The main SPM seasonal peak is observed in the rainy season (June to September in relation to precipitation and sediment transport. A second important peak occurs during the dry season, highlighting the importance of resuspension mechanisms in maintaining high values of SPM. Three different periods are observed: first, a relatively low winds period in the early dry season, when SPM decreases rapidly due to deposition; then, a period of wind-driven resuspension in January‒March; and lastly, an SPM deposition period in April–May, when the monsoon replaces the winter trade wind. Overall, a significant increase of 27% in SPM values is observed between 2000 and 2016 in the Agoufou Lake. The significant spatio-temporal variability in SPM revealed by this study highlights the importance of high resolution optical sensors for continuous monitoring of water quality in

  1. LONG-TERM REMOTE MONITORING OF THREE TYPICAL LAKE AREA VARIATIONS IN THE NORTHWEST CHINA OVER THE PAST 40 YEARS

    Directory of Open Access Journals (Sweden)

    Y. Liu

    2018-04-01

    Full Text Available water resources management and sustainable development strategy, but also provide reference for assessing the impact of climate change and human activities. This paper selects three inland lakes in Northwest China, using Landsat MSS/TM/ETM+/OLI data from 1970 to 2015, Normalized Difference Water Index (NDWI and Modified Normalized Difference Water Index (MNDWI were used to extract lake area and analysed the dynamic trends. Meteorological station rainfall, evaporation and other meteorological data of the lakes were used to analyse reasons for the area change. The results showed that area of Hongjiannao Lake in the past 40 a was reduced, the groundwater impoundment and underground coal mining are the main cause of area reduction; the area of Bosten Lake in recent 40 a showed a decreasing trend after the first increase, the area was mainly affected by the surface runoff and snowmelt; the area of Qinghai Lake in the past 40 a shows a trend of decreasing first and then increasing, the change of its area is mainly affected by regional precipitation and the inflow.

  2. Long-Term Remote Monitoring of Three Typical Lake Area Variations in the Northwest China Over the Past 40 Years

    Science.gov (United States)

    Liu, Y.; Lu, Y.; Li, Y.; Yue, H.

    2018-04-01

    water resources management and sustainable development strategy, but also provide reference for assessing the impact of climate change and human activities. This paper selects three inland lakes in Northwest China, using Landsat MSS/TM/ETM+/OLI data from 1970 to 2015, Normalized Difference Water Index (NDWI) and Modified Normalized Difference Water Index (MNDWI) were used to extract lake area and analysed the dynamic trends. Meteorological station rainfall, evaporation and other meteorological data of the lakes were used to analyse reasons for the area change. The results showed that area of Hongjiannao Lake in the past 40 a was reduced, the groundwater impoundment and underground coal mining are the main cause of area reduction; the area of Bosten Lake in recent 40 a showed a decreasing trend after the first increase, the area was mainly affected by the surface runoff and snowmelt; the area of Qinghai Lake in the past 40 a shows a trend of decreasing first and then increasing, the change of its area is mainly affected by regional precipitation and the inflow.

  3. Use of remotely sensed imagery to map Sudden Oak Death (Phytophthora ramorum) in the Santa Cruz Mountains

    Science.gov (United States)

    Gillis, Trinka

    This project sought a method to map Sudden Oak Death distribution in the Santa Cruz Mountains of California, a coastal mountain range and one of the locations where this disease was first observed. The project researched a method to identify forest affected by SOD using 30 m multi-spectral Landsat satellite imagery to classify tree mortality at the canopy-level throughout the study area, and applied that method to a time series of data to show pattern of spread. A successful methodology would be of interest to scientists trying to identify areas which escaped disease contagion, environmentalists attempting to quantify damage, and land managers evaluating the health of their forests. The more we can learn about the disease, the more chance we have to prevent further spread and damage to existing wild lands. The primary data source for this research was springtime Landsat Climate Data Record surface reflectance data. Non-forest areas were masked out using data produced by the National Land Cover Database and supplemental land cover classification from the Landsat 2011 Climate Data Record image. Areas with other known causes of tree death, as identified by Fire and Resource Assessment Program fire perimeter polygons, and US Department of Agriculture Forest Health Monitoring Program Aerial Detection Survey polygons, were also masked out. Within the remaining forested study area, manually-created points were classified based on the land cover contained by the corresponding Landsat 2011 pixel. These were used to extract value ranges from the Landsat bands and calculated vegetation indices. The range and index which best differentiated healthy from dead trees, SWIR/NIR, was applied to each Landsat scene in the time series to map tree mortality. Results Validation Points, classified using Google Earth high-resolution aerial imagery, were created to evaluate the accuracy of the mapping methodology for the 2011 data.

  4. Determining the Frequency of Dry Lake Bed Formation in Semi-Arid Mongolia From Satellite Data

    Directory of Open Access Journals (Sweden)

    Yuta Demura

    2017-12-01

    Full Text Available In the Mongolian Plateau, the desert steppe, mountains, and dry lake bed surfaces may affect the process of dust storm emissions. Among these three surface types, dry lake beds are considered to contribute a substantial amount of global dust emissions and to be responsible for “hot spots” of dust outbreaks. The land cover types in the study area were broadly divided into three types, namely desert steppe, mountains, and dry lake beds, by a classification based on Normalized Difference Water Index (NDWI calculated from MODIS Terra satellite images, and Digital Elevation Model (DEM. This dry lake beds extracting method using remote sensing offers a new technique for identifying dust hot spots and potential untapped groundwater in the dry lands of the Gobi region. In the study area, frequencies of dry lake bed formation were calculated during the period of 2001 to 2014. The potential dry lake area corresponded well with the length of the river network based on hydrogeological characterization (R2 = 0.77, p < 0.001. We suggest that the threshold between dry lake bed areas and the formation of ephemeral lakes in semi-arid regions is eight days of total precipitation.

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

    Science.gov (United States)

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

    2017-08-15

    Climate change has been shown to increase the number of mountain lakes across various mountain ranges in the World. In Central Asia, and in particular on the territory of Uzbekistan, a detailed assessment of glacier lakes and their evolution over time is, however lacking. For this reason we created the first detailed inventory of mountain lakes of Uzbekistan based on recent (2002-2014) satellite observations using WorldView-2, SPOT5, and IKONOS imagery with a spatial resolution from 2 to 10m. This record was complemented with data from field studies of the last 50years. The previous data were mostly in the form of inventories of lakes, available in Soviet archives, and primarily included localized in-situ data. The inventory of mountain lakes presented here, by contrast, includes an overview of all lakes of the territory of Uzbekistan. Lakes were considered if they were located at altitudes above 1500m and if lakes had an area exceeding 100m 2 . As in other mountain regions of the World, the ongoing increase of air temperatures has led to an increase in lake number and area. Moreover, the frequency and overall number of lake outburst events have been on the rise as well. Therefore, we also present the first outburst assessment with an updated version of well-known approaches considering local climate features and event histories. As a result, out of the 242 lakes identified on the territory of Uzbekistan, 15% are considered prone to outburst, 10% of these lakes have been assigned low outburst potential and the remainder of the lakes have an average level of outburst potential. We conclude that the distribution of lakes by elevation shows a significant influence on lake area and hazard potential. No significant differences, by contrast, exist between the distribution of lake area, outburst potential, and lake location with respect to glaciers by regions. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    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.

  7. Long-range atmospheric transport of persistent organochlorinated compounds from south and mainland south-eastern Asia to a remote mountain site in south-western China.

    Science.gov (United States)

    Xu, Yue; Zhang, Gan; Li, Jun; Chakraborty, Paromita; Li, Hua; Liu, Xiang

    2011-11-01

    A range of organochlorinated compounds have been consumed in China, India and the countries of mainland southeast Asia (MSA). Considering their persistence in the environment and ability in long-range atmospheric transport (LRAT), the potential outflow of these compounds from this region is therefore of great concern in the context of the global distribution of toxic chemicals. As part of a monitoring campaign aimed at investigating the LRAT of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) from southern China, MSA and northern India, atmospheric levels of OCPs and PCBs were measured once a week from October 2005 through December 2006 at Tengchong Mountain (TM), a remote site located in south-western China. The average concentrations of OCPs were found to be higher than those in other remote stations in the Arctic and the Tibetan plateau, except for α-hexachlorocyclohexane (α-HCH). A high level of β-HCH and low α-HCH/β-HCH ratio was attributed to an accidental release of β-HCH from unknown sources, besides obvious evidence of lindane (γ-HCH) and technical HCH usage. Temporal variations of chlordanes and endosulfan were related to the usage pattern of these compounds, as well as LRAT. In contrast, dichlorodiphenyltrichloroethane (DDT) exhibited a relatively minor seasonal variation. The OCP levels at the monitoring site were found to be related to the air parcel back trajectories on the basis of four distinct clusters. Elevated levels of HCHs and DDTs were observed when air parcels originated from northern India where considerable OCP usage was reported recently, while high levels of γ-HCH and TC (trans-chlordane) were mainly associated with air masses from southern China and northern MSA. The study highlighted the high background level of OCPs as well as their temporal patterns of trans-boundary LRAT in the MSA region.

  8. Detecting vegetation cover change on the summit of Cadillac Mountain using multi-temporal remote sensing datasets: 1979, 2001, and 2007.

    Science.gov (United States)

    Kim, Min-Kook; Daigle, John J

    2011-09-01

    This study examines the efficacy of management strategies implemented in 2000 to reduce visitor-induced vegetation impact and enhance vegetation recovery at the summit loop trail on Cadillac Mountain at Acadia National Park, Maine. Using single-spectral high-resolution remote sensing datasets captured in 1979, 2001, and 2007, pre-classification change detection analysis techniques were applied to measure fractional vegetation cover changes between the time periods. This popular sub-alpine summit with low-lying vegetation and attractive granite outcroppings experiences dispersed visitor use away from the designated trail, so three pre-defined spatial scales (small, 0-30 m; medium, 0-60 m; and large, 0-90 m) were examined in the vicinity of the summit loop trail with visitor use (experimental site) and a site chosen nearby in a relatively pristine undisturbed area (control site) with similar spatial scales. Results reveal significant changes in terms of rates of vegetation impact between 1979 and 2001 extending out to 90 m from the summit loop trail with no management at the site. No significant differences were detected among three spatial zones (inner, 0-30 m; middle, 30-60 m; and outer, 60-90 m) at the experimental site, but all were significantly higher rates of impact compared to similar spatial scales at the control site (all p time period. In addition, the advantages and some limitations of using remote sensing technologies are discussed in detecting vegetation change in this setting and potential application to other recreation settings.

  9. Analysis of hepatic deiodinase 2 mRNA levels in natural fish lake populations exposed to different levels of putative thyroid disrupters

    International Nuclear Information System (INIS)

    Jarque, Sergio; Bosch, Carme; Casado, Marta; Grimalt, Joan O.; Raldúa, Demetrio; Piña, Benjamin

    2014-01-01

    Hepatic mRNA levels of the dio2 gene (deiodinase 2), implicated in thyroid hormone homeostasis, were analyzed in trout from six remote lakes in the Pyrenees (Spain) and the Tatra Mountains (Slovakia). Highest levels corresponded to fish from the two coldest lakes in Pyrenees, whereas relatively low levels were found in the Tatra lakes. These values correlated with the presence of highly-brominated polybrominated diphenyl ethers (PBDE) congeners in the muscle of the same animals, reflecting the distribution of these compounds across European mountain ranges. In contrast, cyp1a expression levels, diagnostic for the presence of dioxin-like pollutants, mirrored the distribution of semi-volatile organochlorine compounds, indicating the specificity of the two types of biological responses. Exposure to PDBEs is known to increase transcription of dio2 and other thyroid-related genes in laboratory experiments; we propose that our data reflects the same phenomenon in natural populations, driven by anthropogenic pollutants at the environmental concentrations. - Highlights: • Hepatic deiodinase 2 (dio2) mRNA levels vary among mountain lake trout populations. • High dio2 expression correlated with elevated levels of PBDE 153 and 154 in muscle. • Expression patterns of dio2 and cyp1a diverge among the same fish populations. • Elevated biological responses associated to high loads of specific pollutants. • These data indicate that thyroid disruption may occur in remote ecosystems. - Deionidase dio2 expression as a marker for exposure to putative thyroid disruptors in mountain lake trout

  10. Mapping Asbestos-Cement Roofing with Hyperspectral Remote Sensing over a Large Mountain Region of the Italian Western Alps

    Directory of Open Access Journals (Sweden)

    Federico Frassy

    2014-08-01

    Full Text Available The World Health Organization estimates that 100 thousand people in the world die every year from asbestos-related cancers and more than 300 thousand European citizens are expected to die from asbestos-related mesothelioma by 2030. Both the European and the Italian legislations have banned the manufacture, importation, processing and distribution in commerce of asbestos-containing products and have recommended action plans for the safe removal of asbestos from public and private buildings. This paper describes the quantitative mapping of asbestos-cement covers over a large mountainous region of Italian Western Alps using the Multispectral Infrared and Visible Imaging Spectrometer sensor. A very large data set made up of 61 airborne transect strips covering 3263 km2 were processed to support the identification of buildings with asbestos-cement roofing, promoted by the Valle d’Aosta Autonomous Region with the support of the Regional Environmental Protection Agency. Results showed an overall mapping accuracy of 80%, in terms of asbestos-cement surface detected. The influence of topography on the classification’s accuracy suggested that even in high relief landscapes, the spatial resolution of data is the major source of errors and the smaller asbestos-cement covers were not detected or misclassified.

  11. Altitudinal patterns and controls of trace metal distribution in soils of a remote high mountain, Southwest China.

    Science.gov (United States)

    Li, Rui; Bing, Haijian; Wu, Yanhong; Zhou, Jun; Xiang, Zhongxiang

    2018-02-01

    The aim of this study is to reveal the effects of regional human activity on trace metal accumulation in remote alpine ecosystems under long-distance atmospheric transport. Trace metals (Cd, Pb, and Zn) in soils of the Mt. Luoji, Southwest China, were investigated along a large altitudinal gradient [2200-3850 m above sea level (a.s.l.)] to elaborate the key factors controlling their distribution by Pb isotopic composition and statistical models. The concentrations of Cd, Pb, and Zn in the surface soils (O and A horizons) were relatively low at the altitudes of 3500-3700 m a.s.l. The enrichment factors of trace metals in the surface soils increased with altitude. After normalization for soil organic matter, the concentrations of Cd still increased with altitude, whereas those of Pb and Zn did not show a clear altitudinal trend. The effects of vegetation and cold trapping (CTE) (pollutant enrichment by decreasing temperature with increasing altitude) mainly determined the distribution of Cd and Pb in the O horizon, whereas CTE and bedrock weathering (BW) controlled that of Zn. In the A horizon, the distribution of Cd and Pb depended on the vegetation regulation, whereas that of Zn was mainly related to BW. Human activity, including ores mining and fossil fuels combustion, increased the trace metal deposition in the surface soils. The anthropogenic percentage of Cd, Pb, and Zn quantified 92.4, 67.8, and 42.9% in the O horizon, and 74.5, 33.9, and 24.9% in the A horizon, respectively. The anthropogenic metals deposited at the high altitudes of Mt. Luoji reflected the impact of long-range atmospheric transport on this remote alpine ecosystem from southern and southwestern regions.

  12. Linking land use changes to surface water quality variability in Lake Victoria: some insights from remote sensing

    Science.gov (United States)

    Mugo, R. M.; Limaye, A. S.; Nyaga, J. W.; Farah, H.; Wahome, A.; Flores, A.

    2016-12-01

    The water quality of inland lakes is largely influenced by land use and land cover changes within the lake's catchment. In Africa, some of the major land use changes are driven by a number of factors, which include urbanization, intensification of agricultural practices, unsustainable farm management practices, deforestation, land fragmentation and degradation. Often, the impacts of these factors are observable on changes in the land cover, and eventually in the hydrological systems. When the natural vegetation cover is reduced or changed, the surface water flow patterns, water and nutrient retention capacities are also changed. This can lead to high nutrient inputs into lakes, leading to eutrophication, siltation and infestation of floating aquatic vegetation. To assess the relationship between land use and land cover changes in part of the Lake Victoria Basin, a series of land cover maps were derived from Landsat imagery. Changes in land cover were identified through change maps and statistics. Further, the surface water chlorophyll-a concentration and turbidity were derived from MODIS-Aqua data for Lake Victoria. Chlrophyll-a and turbidity are good proxy indicators of nutrient inputs and siltation respectively. The trends in chlorophyll-a and turbidity concentrations were analyzed and compared to the land cover changes over time. Certain land cover changes related to agriculture and urban development were clearly identifiable. While these changes might not be solely responsible for variability in chlrophyll-a and turbidity concentrations in the lake, they are potentially contributing factors to this problem. This work illustrates the importance of addressing watershed degradation while seeking to solve water quality related problems.

  13. Taphonomy of Early Triassic fish fossils of the Vega-Phroso Siltstone Member of the Sulphur Mountain Formation near Wapiti Lake, British Columbia, Canada

    Directory of Open Access Journals (Sweden)

    Karen Anderson

    2013-10-01

    Full Text Available The taphonomy of fishes living in lacustrine environments has been extensively studied in both the laboratory and the fossil record; the taphonomy of marine fishes, however, is poorly known. Triassic marine fishes with heavy ganoid and cosmoid scales, which provided protection from rapid taphonomic loss, offer a means to examine marine fish taphonomy in the fossil record. Four genera of Early Triassic fishes (the ray-finned actinopterygians Albertonia, Bobasatrania, Boreosomus, and the lobe-finned coelacanth (sarcopterygian, Whiteia from the Wapiti Lake, British Columbia locality of the Lower Triassic Sulphur Mountain Formation were examined in order to gain a better understanding of the taphonomy of fish in marine environments, determine ambient environmental conditions in the region during the Early Triassic, and ascertain the habitat and mode of life of the fish. Results indicate that environmental conditions that contributed to the preservation of the fossil fishes of the current study included deposition in deep, quiet waters, which reduced the odds of disarticulation, colder waters under higher pressure, which slowed decay and limited postmortem floatation, and waters that were anoxic, which discouraged predators and scavengers. In addition, the thickness of the primitive ganoid and cosmoid scales of the fossil fishes also increased their preservation potential. Taphonomic, physiological and environmental indicators suggest that Whiteia, Albertonia, and possibly Bobasatrania lived in deep, cold waters near the oxygen minimum zone, while Boreosomus lived higher in the water column. While the anatomical and physiological characteristics of modern fishes will likely continue to inhibit marine taphonomy studies, examination of ancient fish, particularly those with ganoid or cosmoid scales, may provide future avenues of research to gain a better understanding of marine fish taphonomy and provide a powerful tool to examine ancient fish behavior

  14. Preliminary study of Lake Pontchartrain and vicinity using remotely sensed data from the ERTS-A satellite

    Science.gov (United States)

    Hidalgo, J. U. (Principal Investigator); Smalley, A. E.; Faller, K. H.; Irvin, M. B.

    1973-01-01

    The author has identified the following significant results. During the summer of 1972, huge mats of duckweeds (Lemnaceae) appeared on Lake Pontchartrain, a shallow estuary in southeastern Louisiana. In color infrared photography, duckweeds show a characteristic light lavender color, unlike algal mats or water hyacinth, as observed in low level aerial photography. Although at least five species are present in the area, most water coverage is by Lemna minor and Spirodela oligorrhiza. ERTS-1 imagery shows many areas of bayous, swamps, and marginal waters of Lake Pontchartrain covered with duckweeds. Subsequent passes show a seasonal decreases in duckweeds.

  15. Remote sensing of cyanobacteria-dominant algal blooms and water quality parameters in Zeekoevlei, a small hypertrophic lake, using MERIS

    CSIR Research Space (South Africa)

    Matthews, MW

    2010-09-01

    Full Text Available Eutrophication and cyanobacterial algal blooms present an increasing threat to the health of freshwater ecosystems and to humans who use these resources for drinking and recreation. Remote sensing is being used increasingly as a tool for monitoring...

  16. HYPERSPECTRAL REMOTE SENSING, GPS, AND GIS APPLICATIONS IN OPPORTUNISTIC PLANT SPECIES MONITORING OF GREAT LAKES COASTAL WETLANDS

    Science.gov (United States)

    Coastal wetlands of the Laurentian Great Lakes (LGL) are among the most fragmented and disturbed ecosystems of the world, with a long history of human-induced disturbance. LGL wetlands have undergone losses in the biological diversity that coincides with an increase in the presen...

  17. Comparative Sensor Fusion between Hyperspectral and Multispectral Remote Sensing Data for Monitoring Microcystin Distribution in Lake Erie

    Science.gov (United States)

    Urban growth and agricultural production have caused an influx of nutrients into Lake Erie, leading to eutrophic zones. These conditions result in the formation of algal blooms, some of which are toxic due to the presence of Microcystis (a cyanobacteria), which produces the hepat...

  18. Lake Chad Total Surface Water Area as Derived from Land Surface Temperature and Radar Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Frederick Policelli

    2018-02-01

    Full Text Available Lake Chad, located in the middle of the African Sahel belt, underwent dramatic decreases in the 1970s and 1980s leaving less than ten percent of its 1960s surface water extent as open water. In this paper, we present an extended record (dry seasons 1988–2016 of the total surface water area of the lake (including both open water and flooded vegetation derived using Land Surface Temperature (LST data (dry seasons 2000–2016 from the NASA Terra MODIS sensor and EUMETSAT Meteosat-based LST measurements (dry seasons 1988–2001 from an earlier study. We also examine the total surface water area for Lake Chad using radar data (dry seasons 2015–2016 from the ESA Sentinel-1a mission. For the limited number of radar data sets available to us (18 data sets, we find on average a close match between the estimates from these data and the corresponding estimates from LST, though we find spatial differences in the estimates using the two types of data. We use these spatial differences to adjust the record (dry seasons 2000–2016 from MODIS LST. Then we use the adjusted record to remove the bias of the existing LST record (dry seasons 1988–2001 derived from Meteosat measurements and combine the two records. From this composite, extended record, we plot the total surface water area of the lake for the dry seasons of 1988–1989 through 2016–2017. We find for the dry seasons of 1988–1989 to 2016–2017 that the maximum total surface water area of the lake was approximately 16,800 sq. km (February and May, 2000, the minimum total surface water area of the lake was approximately 6400 sq. km (November, 1990, and the average was approximately 12,700 sq. km. Further, we find the total surface water area of the lake to be highly variable during this period, with an average rate of increase of approximately 143 km2 per year.

  19. Spatio-temporal analysis of floating islands and their behavioral changes in Loktak Lake with respect to biodiversity using remote sensing and GIS techniques.

    Science.gov (United States)

    Kangabam, Rajiv Das; Selvaraj, Muthu; Govindaraju, Munisamy

    2018-02-06

    The presence of floating islands is a unique characteristic of Loktak Lake. Floating islands play a significant role in ecosystem services and ecological processes and functioning. Rapid urbanization, industrialization, and a demand for more resources have led to changes in the landscape patterns at Loktak Lake in past three decades, thereby degrading and threatening the fragile ecosystem. The aim of the present study is to assess the changes in land use practices of the Phumdis by analyzing data from the past 38 years with remote sensing techniques. Landsat images from 1977, 1988, 1999 and an Indian remote sensing image from 2015 were used to assess the land use/land cover changes. The methodology adopted is a supervised classification using the maximum likelihood technique in ERDAS software. Five land used classes were employed: open water bodies, agricultural areas, Phumdis with thick vegetation, and Phumdis with thin vegetation and settlements. The results indicate that the highest loss of land used class was in Phumdis with thin vegetation (49.38 km 2 ) followed by Phumdis with thick vegetation (8.59 km 2 ), while there was an overall increase in open water bodies (27.00 km 2 ), agricultural areas (25.33 km 2 ), and settlement (5.75 km 2 ). Our study highlights the loss of floating islands from the Loktak as a major concern that will lead to the destruction of the only "floating national park in the world." There is a high probability of extinction of the Sangai, an important keystone species found in the Indo-Burma biodiversity hotspot, if floating islands are not protected through sustainable development.

  20. Growth dynamics of tree-line and lake-shore Scots pine (Pinus sylvestris L. in the central Scandinavian Mountains during the Medieval Climate Anomaly and the early Little Ice Age

    Directory of Open Access Journals (Sweden)

    Hans W Linderholm

    2014-05-01

    Full Text Available Trees growing at their altitudinal or latitudinal distribution in Fennoscandia have been widely used to reconstruct warm season temperatures, and the region hosts some of the world’s longest tree-ring chronologies. These multi-millennial long chronologies have mainly been built from tree remains found in lakes (subfossil wood from lake-shore trees. We used a unique dataset of Scots pine tree-ring data collected from wood remains found on a mountain slope in the central Scandinavian Mountains, yielding a chronology spanning over much of the last 1200 years. This data was compared with a local subfossil wood chronology with the aim to 1 describe growth variability in two environments during the Medieval Climate Anomaly (MCA and the early Little Ice Age (LIA, and 2 investigate differences in growth characteristics during these contrasting periods. It was shown that the local tree-line during both the MCA and early LIA was almost 150 m higher that at present. Based on living pines from the two environments, tree-line pine growth was strongly associated with mid-summer temperatures, while the lake-shore trees showed an additional response to summer precipitation. During the MCA, regarded to be a period of favourable climate in the region, the tree-ring data from both environments showed strong coherency and moderate growth variability. In the early LIA, the two chronologies were less coherent, with the tree-line chronology showing more variability, suggesting different growth responses in the two environments during this period of less favourable growing conditions. Our results indicate that tree-ring width chronologies mainly based on lake-shore trees may need to be re-evaluated.

  1. Remote sensing data to classify functional groups of vegetation and their distribution and abundance in a semiarid mountain watershed, Idaho, USA

    Science.gov (United States)

    Loughridge, R. E.; Benner, S. G.; McNamara, J. P.; Flores, A. N.

    2012-12-01

    In water-limited montane ecosystems, topography is a significant driver of energy balance and soil moisture and therefore governs the distribution and abundance of terrestrial vegetation. Few studies have made a concerted effort to quantify spatial patterns in vegetation along physiographic gradients that control microclimate such as slope, elevation, and aspect. Furthermore, spectral mixing of different vegetation species within individual visible and near-infrared remote sensing pixels makes it difficult to constrain the temporal growth and senescence of individual plant functional types. We report on a study that seeks to understand the interacting roles of topography, soil moisture, and solar radiation on the distribution of different plant functional types within the Dry Creek Experimental Watershed (DCEW). Boise State University maintains the 27 km2 watershed which is located in the Boise Front Mountains of southwest Idaho. It is qualitatively observed in DCEW that low elevations are dominated by sage-steppe ecosystems and high elevations transition to conifer forests. It is also observed that aspect has a major control in which sage-steppe is evident at high elevations on south facing slopes conversely from north facing slopes. To quantify these trends we measured percent ground cover of functional groups (i.e. forbs, grass, shrubs, etc.) at 77 sites within DCEW spanning a large gradient in the controlling biophysiographic variables. In addition, vegetation water content (VWC) and spectral reflectance from the 325 to 1075 nm wavelengths was collected for specific vegetation types at eight permanent soil moisture monitoring sites contained in DCEW throughout the 2012 green-up/senescence transition. To develop a watershed-wide classification we built a supervised multilayer perceptron (MLP) backpropagating artificial neural network (ANN) using temporal Landsat 5 images to classify 4 major groups: sage-steppe, Douglas fir, ponderosa pine, and deciduous trees

  2. Integrating biophysical and socioeconomic information for prioritizing watersheds in a Kashmir Himalayan lake: a remote sensing and GIS approach.

    Science.gov (United States)

    Badar, Bazigha; Romshoo, Shakil A; Khan, M A

    2013-08-01

    Dal Lake, a cradle of Kashmiri civilization has strong linkage with socioeconomics of the state of Jammu and Kashmir. During last few decades, anthropogenic pressures in Dal Lake Catchment have caused environmental deterioration impairing, inter-alia, sustained biotic communities and water quality. The present research was an integrated impact analysis of socioeconomic and biophysical processes at the watershed level on the current status of Dal Lake using multi-sensor and multi-temporal satellite data, simulation modelling together with field data verification. Thirteen watersheds (designated as 'W1-W13') were identified and investigated for land use/land cover change detection, quantification of erosion and sediment loads and socioeconomic analysis (total population, total households, literacy rate and economic development status). All the data for the respective watersheds was integrated into the GIS environment based upon multi-criteria analysis and knowledge-based weightage system was adopted for watershed prioritization based on its factors and after carefully observing the field situation. The land use/land cover change detection revealed significant changes with a uniform trend of decreased vegetation and increased impervious surface cover. Increased erosion and sediment loadings were recorded for the watersheds corresponding to their changing land systems, with bare and agriculture lands being the major contributors. The prioritization analysis revealed that W5 > W2 > W6 > W8 > W1 ranked highest in priority and W13 > W3 > W4 > W11 > W7 under medium priority. W12 > W9 > W10 belonged to low-priority category. The integration of the biophysical and the socioeconomic environment at the watershed level using modern geospatial tools would be of vital importance for the conservation and management strategies of Dal Lake ecosystem.

  3. Mercury biomagnification and the trophic structure of the ichthyofauna from a remote lake in the Brazilian Amazon.

    Science.gov (United States)

    Azevedo-Silva, Claudio Eduardo; Almeida, Ronaldo; Carvalho, Dario P; Ometto, Jean P H B; de Camargo, Plínio B; Dorneles, Paulo R; Azeredo, Antonio; Bastos, Wanderley R; Malm, Olaf; Torres, João P M

    2016-11-01

    The present study assesses mercury biomagnification and the trophic structure of the ichthyofauna from the Puruzinho Lake, Brazilian Amazon. In addition to mercury determination, the investigation comprised the calculation of Trophic Magnification Factor (TMF) and Trophic Magnification Slope (TMS), through the measurements of stable isotopes of carbon (δ 13 C) and nitrogen (δ 15 N) in fish samples. These assessments were executed in two different scenarios, i.e., considering (1) all fish species or (2) only the resident fish (excluding the migratory species). Bottom litter, superficial sediment and seston were the sources used for generating the trophic position (TP) data used in the calculation of the TMF. Samples from 84 fish were analysed, comprising 13 species, which were categorized into four trophic guilds: iliophagous, planktivorous, omnivorous and piscivorous fish. The δ 13 C values pointed to the separation of the ichthyofauna into two groups. One group comprised iliophagous and planktivorous species, which are linked to the food chains of phytoplankton and detritus. The other group was composed by omnivorous and piscivorous fish, which are associated to the trophic webs of phytoplankton, bottom litter, detritus, periphyton, as well as to food chains of igapó (blackwater-flooded Amazonian forests). The TP values suggest that the ichthyofauna from the Puruzinho Lake is part of a short food web, with three well-characterized trophic levels. Mercury concentrations and δ 13 C values point to multiple sources for Hg input and transfer. The similarity in Hg levels and TP values between piscivorous and planktivorous fish suggests a comparable efficiency for the transfer of this metal through pelagic and littoral food chains. Regarding the two abovementioned scenarios, i.e., considering (1) the entire ichthyofauna and (2) only the resident species, the TMF values were 5.25 and 4.49, as well as the TMS values were 0.21 and 0.19, respectively. These findings

  4. Remote Sensing Assessment of Forest Disturbance across Complex Mountainous Terrain: The Pattern and Severity of Impacts of Tropical Cyclone Yasi on Australian Rainforests

    Directory of Open Access Journals (Sweden)

    Robinson I. Negrón-Juárez

    2014-06-01

    Full Text Available Topography affects the patterns of forest disturbance produced by tropical cyclones. It determines the degree of exposure of a surface and can alter wind characteristics. Whether multispectral remote sensing data can sense the effect of topography on disturbance is a question that deserves attention given the multi-scale spatial coverage of these data and the projected increase in intensity of the strongest cyclones. Here, multispectral satellite data, topographic maps and cyclone surface wind data were used to study the patterns of disturbance in an Australian rainforest with complex mountainous terrain produced by tropical cyclone Yasi (2011. The cyclone surface wind data (H*wind was produced by the Hurricane Research Division of the National Oceanic and Atmospheric Administration (HRD/NOAA, and this was the first time that this data was produced for a cyclone outside of United States territory. A disturbance map was obtained by applying spectral mixture analyses on satellite data and presented a significant correlation with field-measured tree mortality. Our results showed that, consistent with cyclones in the southern hemisphere, multispectral data revealed that forest disturbance was higher on the left side of the cyclone track. The highest level of forest disturbance occurred in forests along the path of the cyclone track (±30°. Levels of forest disturbance decreased with decreasing slope and with an aspect facing off the track of the cyclone or away from the dominant surface winds. An increase in disturbance with surface elevation was also observed. However, areas affected by the same wind intensity presented increased levels of disturbance with increasing elevation suggesting that complex terrain interactions act to speed up wind at higher elevations. Yasi produced an important offset to Australia’s forest carbon sink in 2010. We concluded that multispectral data was sensitive to the main effects of complex topography on disturbance

  5. Remote sensing for water quality

    International Nuclear Information System (INIS)

    Giardino, Claudia

    2006-01-01

    The application of remote sensing to the study of lakes is begun in years 80 with the lunch of the satellites of second generation. Many experiences have indicated the contribution of remote sensing for the limnology [it

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

    Science.gov (United States)

    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

  7. Peculiarities of high-altitude landscapes formation in the Small Caucasus mountains

    Science.gov (United States)

    Trifonova, Tatiana

    2014-05-01

    Various mountain systems differ in character of landscapes and soil. Basic problem of present research: conditions and parameters determining the development of various landscapes and soils in mountain areas. Our research object is the area of Armenia where Small Caucasus, a part of Armenian upland is located. The specific character of the area is defined by the whole variety of all mountain structures like fold, block folding mountain ridges, volcanic upland, individual volcanoes, and intermountain depressions. As for the climate, the area belongs to dry subtropics. We have studied the peculiarities of high-altitude landscapes formation and mountain river basins development. We have used remote sensing data and statistic database of climatic parameters in this research. Field observations and landscape pictures analysis of space images allow distinguishing three types of mountain geosystems clearly: volcanic massifs, fold mountainous structures and closed high mountain basins - area of the lakes. The distribution of precipitation according to altitude shows some peculiarities. It has been found that due to this factor the investigated mountain area may be divided into three regions: storage (fold) mountainous area; Ararat volcanic area (southern macro exposure); closed high mountainous basin-area of the lake Sevan. The mountainous nature-climatic vertical landscapes appear to be horizontally oriented and they are more or less equilibrium (stable) geosystems, where the stable functional relationship between the landscape components is formed. Within their limits, definite bioclimatic structure of soil is developed. Along the slopes of fold mountains specific landscape shapes like litho-drainage basins are formed. They are intensively developing like relatively independent vertical geosystems. Mechanism of basin formation is versatile resulting in formation of the polychronous soil mantle structure. Landscapes and soils within the basin are of a different age, since

  8. Fractionation of cesium isotopes and 90Sr in snowmelt run-off and lake waters from a contaminated Norwegian mountain catchment

    International Nuclear Information System (INIS)

    Salbu, B.; Bjoernstad, H.E.; Brittain, J.E.

    1992-01-01

    Cesium isotopes and 90 Sr have been determined in the inflow and outflow rivers of a Norwegian subalpine lake. The lake is situated in an area contaminated by Chernobyl fallout. Sampling was carried out during the spring peak discharge period associated with snowmelt. Transported coarse particulate plant material was collected by traps. Particles and colloids were removed from water samples by hollow fibre ultrafiltration. The results illustrate that run-off during the spring snowmelt is an important pathway for these radionuclides. The cesium isotopes are predominantly transported as colloids, while 90 Sr is present in the form of low molecular weight mobile species. Based on lake budget calculations, more than 50% of the cesium input is retained in the lake, while more than 90% of the 90 Sr is transported through the lake and into lower parts of the drainage system. (author) 16 refs.; 6 figs.; 3 tabs

  9. Analyzing landscape changes in the Bafa Lake Nature Park of Turkey using remote sensing and landscape structure metrics.

    Science.gov (United States)

    Esbah, Hayriye; Deniz, Bulent; Kara, Baris; Kesgin, Birsen

    2010-06-01

    Bafa Lake Nature Park is one of Turkey's most important legally protected areas. This study aimed at analyzing spatial change in the park environment by using object-based classification technique and landscape structure metrics. SPOT 2X (1994) and ASTER (2005) images are the primary research materials. Results show that artificial surfaces, low maqui, garrigue, and moderately high maqui covers have increased and coniferous forests, arable lands, permanent crop, and high maqui covers have decreased; coniferous forest, high maqui, grassland, and saline areas are in a disappearance stage of the land transformation; and the landscape pattern is more fragmented outside the park boundaries. The management actions should support ongoing vegetation regeneration, mitigate transformation of vegetation structure to less dense and discontinuous cover, control the dynamics at the agricultural-natural landscape interface, and concentrate on relatively low but steady increase of artificial surfaces.

  10. 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.

    Directory of Open Access Journals (Sweden)

    Hajime Ohtsuki

    Full Text Available 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.

  11. Rocky Mountain Riparian Digest

    Science.gov (United States)

    Deborah M. Finch

    2008-01-01

    The Rocky Mountain Riparian Digest presents the many facets of riparian research at the station. Included are articles about protecting the riparian habitat, the social and economic values of riparian environments, watershed restoration, remote sensing tools, and getting kids interested in the science.

  12. Rock cliffs hazard analysis based on remote geostructural surveys: The Campione del Garda case study (Lake Garda, Northern Italy)

    Science.gov (United States)

    Ferrero, A. M.; Migliazza, M.; Roncella, R.; Segalini, A.

    2011-02-01

    The town of Campione del Garda (located on the west coast of Lake Garda) and its access road have been historically subject to rockfall phenomena with risk for public security in several areas of the coast. This paper presents a study devoted to the determination of risk for coastal cliffs and the design of mitigation measures. Our study was based on statistical rockfall analysis performed with a commercial code and on stability analysis of rock slopes based on the key block method. Hazard from block kinematics and rock-slope failure are coupled by applying the Rockfall Hazard Assessment Procedure (RHAP). Because of the huge dimensions of the slope, its morphology and the geostructural survey were particularly complicated and demanding. For these reasons, noncontact measurement methods, based on aerial photogrammetry by helicopter, were adopted. A special software program, developed by the authors, was applied for discontinuity identification and for their orientation measurements. The potentially of aerial photogrammetic survey in rock mechanic application and its improvement in the rock mass knowledge is analysed in the article.

  13. Do it yourself remote sensing: Generating an inexpensive, high tech, real science lake mapping project for the classroom

    Science.gov (United States)

    Metzger, Stephen M.

    1993-01-01

    The utilization of modest equipment and software revealed bottom contours and water column conditions of a dynamic water body. Classroom discussions of field techniques and equipment capabilities followed by exercises with the data sets in cause-and-effect analysis all contributed to participatory education in the process of science. This project is presented as a case study of the value of engaging secondary and collegiate level students in planning, executing and appraising a real world investigation which they can directly relate to. A 1 km wide bay, experiencing marsh inflow, along an 8 km long lake situated 120 km north of Ottawa, Canada, on the glaciated Canadian Precambrian Shield was mapped in midsummer for submerged topography, bottom composition, temperature profile, turbudity, dissolved oxygen and biota distribution. Low level aerial photographs scanned into image processing software are permitting spatial classification of bottom variations in biology and geology. Instrumentation consisted of a portable sport fishing SONAR depth finder, an electronic lead line multiprobe with photocell, thermistor and dissolved oxygen sensors, a selective depth water sampler, portable pH meter, an underwater camera mounted on a home-made platform with a bottom-contact trigger and a disposable underwater camera for shallow survey work. Sampling transects were referenced using a Brunton hand transit triangulating several shore markers.

  14. Land cover mapping at Alkali Flat and Lake Lucero, White Sands, New Mexico, USA using multi-temporal and multi-spectral remote sensing data

    Science.gov (United States)

    Ghrefat, Habes A.; Goodell, Philip C.

    2011-08-01

    The goal of this research is to map land cover patterns and to detect changes that occurred at Alkali Flat and Lake Lucero, White Sands using multispectral Landsat 7 Enhanced Thematic Mapper Plus (ETM+), Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Advanced Land Imager (ALI), and hyperspectral Hyperion and Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data. The other objectives of this study were: (1) to evaluate the information dimensionality limits of Landsat 7 ETM+, ASTER, ALI, Hyperion, and AVIRIS data with respect to signal-to-noise and spectral resolution, (2) to determine the spatial distribution and fractional abundances of land cover endmembers, and (3) to check ground correspondence with satellite data. A better understanding of the spatial and spectral resolution of these sensors, optimum spectral bands and their information contents, appropriate image processing methods, spectral signatures of land cover classes, and atmospheric effects are needed to our ability to detect and map minerals from space. Image spectra were validated using samples collected from various localities across Alkali Flat and Lake Lucero. These samples were measured in the laboratory using VNIR-SWIR (0.4-2.5 μm) spectra and X-ray Diffraction (XRD) method. Dry gypsum deposits, wet gypsum deposits, standing water, green vegetation, and clastic alluvial sediments dominated by mixtures of ferric iron (ferricrete) and calcite were identified in the study area using Minimum Noise Fraction (MNF), Pixel Purity Index (PPI), and n-D Visualization. The results of MNF confirm that AVIRIS and Hyperion data have higher information dimensionality thresholds exceeding the number of available bands of Landsat 7 ETM+, ASTER, and ALI data. ASTER and ALI data can be a reasonable alternative to AVIRIS and Hyperion data for the purpose of monitoring land cover, hydrology and sedimentation in the basin. The spectral unmixing analysis and dimensionality eigen

  15. Glacial lakes in Austria - Distribution and formation since the Little Ice Age

    Science.gov (United States)

    Buckel, J.; Otto, J. C.; Prasicek, G.; Keuschnig, M.

    2018-05-01

    Glacial lakes constitute a substantial part of the legacy of vanishing mountain glaciation and act as water storage, sediment traps and sources of both natural hazards and leisure activities. For these reasons, they receive growing attention by scientists and society. However, while the evolution of glacial lakes has been studied intensively over timescales tied to remote sensing-based approaches, the longer-term perspective has been omitted due a lack of suitable data sources. We mapped and analyzed the spatial distribution of glacial lakes in the Austrian Alps. We trace the development of number and area of glacial lakes in the Austrian Alps since the Little Ice Age (LIA) based on a unique combination of a lake inventory and an extensive record of glacier retreat. We find that bedrock-dammed lakes are the dominant lake type in the inventory. Bedrock- and moraine-dammed lakes populate the highest landscape domains located in cirques and hanging valleys. We observe lakes embedded in glacial deposits at lower locations on average below 2000 m a.s.l. In general, the distribution of glacial lakes over elevation reflects glacier erosional and depositional dynamics rather than the distribution of total area. The rate of formation of new glacial lakes (number, area) has continuously accelerated over time with present rates showing an eight-fold increase since LIA. At the same time the total glacier area decreased by two-thirds. This development coincides with a long-term trend of rising temperatures and a significant stepping up of this trend within the last 20 years in the Austrian Alps.

  16. A 15,000 year record of vegetation and climate change from a treeline lake in the Rocky Mountains, Wyoming, USA

    Science.gov (United States)

    Scott A. Mensing; John L. Korfmacher; Thomas Minckley; Robert C. Musselman

    2012-01-01

    Future climate projections predict warming at high elevations that will impact treeline species, but complex topographic relief in mountains complicates ecologic response, and we have a limited number of long-term studies examining vegetation change related to climate. In this study, pollen and conifer stomata were analyzed from a 2.3 m sediment core extending to 15,...

  17. Land use/cover disturbance due to tourism in Jeseníky Mountain, Czech Republic: A remote sensing and GIS based approach

    OpenAIRE

    Mukesh Singh Boori; Vít Voženílek; Komal Choudhary

    2015-01-01

    The Jeseníky Mountains tourism in Czech Republic is unique for its floristic richness. This is caused mainly by the altitude division and polymorphism of the landscape, climate and soil structure. This study assesses the impacts of tourism on the land cover in the Jeseníky Mountain region by comparing multi-temporal Landsat imageries (1991, 2001 and 2013) to describe the rate and extent of land-cover changes. This was achieved through spectral classification of different land cover classes an...

  18. Long-term dynamics of watershed leaching and lake sediment sequestration of rare earth elements following deglaciation of two mountain watersheds.

    Czech Academy of Sciences Publication Activity Database

    Norton, S. A.; Pierret, M.C.; Kopáček, Jiří; Handley, M.J.; Perry, R.H.

    2016-01-01

    Roč. 55, č. 3 (2016), s. 209-222 ISSN 0921-2728 Institutional support: RVO:60077344 Keywords : rare earth elements * aluminum * phosphorus * lake sediment * weathering Subject RIV: DJ - Water Pollution ; Quality Impact factor: 2.017, year: 2016

  19. Lake oxygen isotopes as recorders of North American Rocky Mountain hydroclimate: Holocene patterns and variability at multi-decadal to millennial time scales

    Science.gov (United States)

    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

  20. Lake oxygen isotopes as recorders of North American Rocky Mountain hydroclimate: Holocene patterns and variability at multi-decadal to millennial time scales

    Science.gov (United States)

    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

  1. The relative importance of the planktonic food web in the carbon cycle of an oligotrophic mountain lake in a poorly vegetated catchment (Redó, Pyrenees

    Directory of Open Access Journals (Sweden)

    Lluís CAMARERO

    1999-08-01

    Full Text Available The biological activity of the planktonic community of lake Redó, expressed in terms of carbon fluxes, was measured and compared to the changes in DIC, DOC and POC in the water column. Planktonic photosynthesis ranged between c. 0.01 - 0.3 μg C m-2 h-1. Release of EOC phytoplankton was highly variable, between 5 and 80% of total fixation. Bacterial uptake of EOC ranged between 1-20% of total fixation. Bacterial activities were, in absolute numbers, very low: 0.005±0.003 μg C m-2 h-1, in contrast with the higher grazing rates on bacteria of 0.036±0.021 μg C m-2 h-1. Respiration and diffusion of CO2 to the atmosphere seem to be the main processes controlling DIC concentration. DOC and POC concentrations were highly correlated, and their fluxes presented large fluctuations. These changes in DOC are larger than those due to the processes we have measured. Other processes that might affect DOC include diffusion from sediments, inputs from the catchment, uptake by mixotrophic algae and zooplankton, bacterial respiration, UV photoxidation, and flocculation. Lake Redó seems to act in general terms as an heterotrophic system: respiration is higher than photosynthesis, and the budget is balanced by the import of DOC and, to a lesser extent, POC. Most of the carbon seems to be ultimately released to atmosphere, since little is accumulated in sediments. The estimates of diffusive fluxes agreed with this hypothesis. At this stage, the comparison of biogeochemical budgets with biological activity measurements only serves as a rough approximation of the main pathways in the C cycling in the lake, and to point the issues that need further research in order to calculate the C budget in the lake with accuracy.

  2. Remotely Sensed Estimation of Net Primary Productivity (NPP and Its Spatial and Temporal Variations in the Greater Khingan Mountain Region, China

    Directory of Open Access Journals (Sweden)

    Qiang Zhu

    2017-07-01

    Full Text Available We improved the CASA model based on differences in the types of land use, the values of the maximum light use efficiency, and the calculation methods of solar radiation. Then, the parameters of the model were examined and recombined into 16 cases. We estimated the net primary productivity (NPP using the NDVI3g dataset, meteorological data, and vegetation classification data from the Greater Khingan Mountain region, China. We assessed the accuracy and temporal-spatial distribution characteristics of NPP in the Greater Khingan Mountain region from 1982 to 2013. Based on a comparison of the results of the 16 cases, we found that different values of maximum light use efficiency affect the estimation more than differences in the fraction of photosynthetically active radiation (FPAR. However, the FPARmax and the constant Tε2 values did not show marked effects. Different schemes were used to assess different model combinations. Models using a combination of parameters established by scholars from China and the United States produced different results and had large errors. These ideas are meaningful references for the estimation of NPP in other regions. The results reveal that the annual average NPP in the Greater Khingan Mountain region was 760 g C/m2·a in 1982–2013 and that the inter-annual fluctuations were not dramatic. The NPP estimation results of the 16 cases exhibit an increasing trend. In terms of the spatial distribution of the changes, the model indicated that the values in 75% of this area seldom or never increased. Prominent growth occurred in the areas of Taipingling, Genhe, and the Oroqen Autonomous Banner. Notably, NPP decreased in the southeastern region of the Greater Khingan Mountains, the Hulunbuir Pasture Land, and Holingol.

  3. Regional Analysis of the Hazard Level of Glacial Lakes in the Cordillera Blanca, Peru

    Science.gov (United States)

    Chisolm, Rachel E.; Jhon Sanchez Leon, Walter; McKinney, Daene C.; Cochachin Rapre, Alejo

    2016-04-01

    The Cordillera Blanca mountain range is the highest in Peru and contains many of the world's tropical glaciers. This region is severely impacted by climate change causing accelerated glacier retreat. Secondary impacts of climate change on glacier retreat include stress on water resources and the risk of glacial lake outburst floods (GLOFs) from the many lakes that are forming and growing at the base of glaciers. A number of GLOFs originating from lakes in the Cordillera Blanca have occurred over the last century, several of which have had catastrophic impacts on cities and communities downstream. Glaciologists and engineers in Peru have been studying the lakes of the Cordillera Blanca for many years and have identified several lakes that are considered dangerous. However, a systematic analysis of all the lakes in the Cordillera Blanca has never before been attempted. Some methodologies for this type of systematic analysis have been proposed (eg. Emmer and Vilimek 2014; Wang, et al. 2011), but as yet they have only been applied to a few select lakes in the Cordillera Blanca. This study uses remotely sensed data to study all of the lakes of the Glacial Lake Inventory published by the Glaciology and Water Resources Unit of Peru's National Water Authority (UGRH 2011). The objective of this study is to assign a level of potential hazard to each glacial lake in the Cordillera Blanca and to ascertain if any of the lakes beyond those that have already been studied might pose a danger to nearby populations. A number of parameters of analysis, both quantitative and qualitative, have been selected to assess the hazard level of each glacial lake in the Cordillera Blanca using digital elevation models, satellite imagery, and glacier outlines. These parameters are then combined to come up with a preliminary assessment of the hazard level of each lake; the equation weighting each parameter draws on previously published methodologies but is tailored to the regional characteristics

  4. Klimatska pogojenost debelinskega prirastka dreves ob slovenskih visokogorskih alpskih jezerih = Climatic conditioning or radial increments of trees near Slovenian high-mountainous Alpine lakes

    Directory of Open Access Journals (Sweden)

    Darko Ogrin

    1998-01-01

    Full Text Available Analysed by means of standard dendrochronological and dendroclimatological processes were about 100 spruce and larch samples from the lake areas of Jezera on Planina pri Jezeru, Jezera v Ledvicah and Krnsko Jezero, all in the Julian Alps. Local chronologies mainly include the period from 1920 onwards. Correlation between radial increments and climatic data confirmed certain general anticipations about the relation between climate and increments in the upper forest-line zone, and concurrently exposed the specific influence of local, including non-climatic factors on the growth which can not be satisfactory comprised in dendroclimatological analysis.

  5. Terrestrial CDOM in Lakes of Yamal Peninsula: Connection to Lake and Lake Catchment Properties

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    Yury Dvornikov

    2018-01-01

    Full Text Available In this study, we analyze interactions in lake and lake catchment systems of a continuous permafrost area. We assessed colored dissolved organic matter (CDOM absorption at 440 nm (a(440CDOM and absorption slope (S300–500 in lakes using field sampling and optical remote sensing data for an area of 350 km2 in Central Yamal, Siberia. Applying a CDOM algorithm (ratio of green and red band reflectance for two high spatial resolution multispectral GeoEye-1 and Worldview-2 satellite images, we were able to extrapolate the a(λCDOM data from 18 lakes sampled in the field to 356 lakes in the study area (model R2 = 0.79. Values of a(440CDOM in 356 lakes varied from 0.48 to 8.35 m−1 with a median of 1.43 m−1. This a(λCDOM dataset was used to relate lake CDOM to 17 lake and lake catchment parameters derived from optical and radar remote sensing data and from digital elevation model analysis in order to establish the parameters controlling CDOM in lakes on the Yamal Peninsula. Regression tree model and boosted regression tree analysis showed that the activity of cryogenic processes (thermocirques in the lake shores and lake water level were the two most important controls, explaining 48.4% and 28.4% of lake CDOM, respectively (R2 = 0.61. Activation of thermocirques led to a large input of terrestrial organic matter and sediments from catchments and thawed permafrost to lakes (n = 15, mean a(440CDOM = 5.3 m−1. Large lakes on the floodplain with a connection to Mordy-Yakha River received more CDOM (n = 7, mean a(440CDOM = 3.8 m−1 compared to lakes located on higher terraces.

  6. Datasets related to in-land water for limnology and remote sensing applications: distance-to-land, distance-to-water, water-body identifier and lake-centre co-ordinates.

    Science.gov (United States)

    Carrea, Laura; Embury, Owen; Merchant, Christopher J

    2015-11-01

    Datasets containing information to locate and identify water bodies have been generated from data locating static-water-bodies with resolution of about 300 m (1/360 ∘ ) recently released by the Land Cover Climate Change Initiative (LC CCI) of the European Space Agency. The LC CCI water-bodies dataset has been obtained from multi-temporal metrics based on time series of the backscattered intensity recorded by ASAR on Envisat between 2005 and 2010. The new derived datasets provide coherently: distance to land, distance to water, water-body identifiers and lake-centre locations. The water-body identifier dataset locates the water bodies assigning the identifiers of the Global Lakes and Wetlands Database (GLWD), and lake centres are defined for in-land waters for which GLWD IDs were determined. The new datasets therefore link recent lake/reservoir/wetlands extent to the GLWD, together with a set of coordinates which locates unambiguously the water bodies in the database. Information on distance-to-land for each water cell and the distance-to-water for each land cell has many potential applications in remote sensing, where the applicability of geophysical retrieval algorithms may be affected by the presence of water or land within a satellite field of view (image pixel). During the generation and validation of the datasets some limitations of the GLWD database and of the LC CCI water-bodies mask have been found. Some examples of the inaccuracies/limitations are presented and discussed. Temporal change in water-body extent is common. Future versions of the LC CCI dataset are planned to represent temporal variation, and this will permit these derived datasets to be updated.

  7. An approach for estimating the breach probabilities of moraine-dammed lakes in the Chinese Himalayas using remote-sensing data

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    X. Wang

    2012-10-01

    Full Text Available To make first-order estimates of the probability of moraine-dammed lake outburst flood (MDLOF and prioritize the probabilities of breaching posed by potentially dangerous moraine-dammed lakes (PDMDLs in the Chinese Himalayas, an objective approach is presented. We first select five indicators to identify PDMDLs according to four predesigned criteria. The climatic background was regarded as the climatic precondition of the moraine-dam failure, and under different climatic preconditions, we distinguish the trigger mechanisms of MDLOFs and subdivide them into 17 possible breach modes, with each mode having three or four components; we combined the precondition, modes and components to construct a decision-making tree of moraine-dam failure. Conversion guidelines were established so as to quantify the probabilities of components of a breach mode employing the historic performance method combined with expert knowledge and experience. The region of the Chinese Himalayas was chosen as a study area where there have been frequent MDLOFs in recent decades. The results show that the breaching probabilities (P of 142 PDMDLs range from 0.037 to 0.345, and they can be further categorized as 43 lakes with very high breach probabilities (P ≥ 0.24, 47 lakes with high breach probabilities (0.18 ≤ P < 0.24, 24 lakes with mid-level breach probabilities (0.12 ≤ P < 0.18, 24 lakes with low breach probabilities (0.06 ≤ P < 0.12, and four lakes with very low breach probabilities (p < 0.06.

  8. Land use/cover disturbance due to tourism in Jeseníky Mountain, Czech Republic: A remote sensing and GIS based approach

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    Mukesh Singh Boori

    2015-06-01

    Full Text Available The Jeseníky Mountains tourism in Czech Republic is unique for its floristic richness. This is caused mainly by the altitude division and polymorphism of the landscape, climate and soil structure. This study assesses the impacts of tourism on the land cover in the Jeseníky Mountain region by comparing multi-temporal Landsat imageries (1991, 2001 and 2013 to describe the rate and extent of land-cover changes. This was achieved through spectral classification of different land cover classes and by assessing the change in forest; settlements; pasture and agriculture in relation to increasing distances (5, 10 and 15 km from three tourism sites with the help of ArcGIS software. The results indicate that the area was deforested (11.13% from 1991 to 2001 than experienced forest regrowth (6.71% from 2001 to 2013. In the first decade pasture and agriculture areas increased and then in next decade decreased. The influence of tourism facilities on land cover is also variable. Around each of the tourism site sampled, there was a general trend of forest removal decreasing as the distance from each village increased, which indicates tourism does have a negative impact on forests. However there was an opposite trend from 2001 to 2013 that indicates conservation area. The interplay among global (tourism, climate, regional (national policies, large-river management and local (construction and agriculture, energy and water sources to support the tourism industry factors drives a distinctive but complex pattern of land-use and land-cover disturbance.

  9. A semi-automated approach for mapping geomorphology of El Bardawil Lake, Northern Sinai, Egypt, using integrated remote sensing and GIS techniques

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    Nabil Sayed Embabi

    2014-06-01

    Full Text Available Among the other coastal lakes of the Mediterranean northern coast of Egypt, Bardawil Lake is a unique lagoon, as it is fed only by seawater. The lagoon is composed of two main basins, and several other internal small basins interconnected to one another. Although the general geomorphologic characteristics are treated in some regional studies, we used a semi-automated approach based on a wide variety of digital image processing for mapping the major geomorphological landforms of the lake on a medium scale of 1:250,000. The approach is based primarily on data fusion of Landsat ETM+ image, and validated by other ancillary spatial data (e.g. topographic maps, Google images and GPS in situ data. Interpretations of high resolution space images by Google Earth and the large-scale topographic maps (1:25,000, in specific, revealed new microforms and some detailed geomorphologic aspects with the aid of GPS measurements. Small sand barriers, submerged sand dunes, tidal channels, fans and flats, and micro-lagoons are the recurrent forms in the lake. The approach used in this study could be widely applied to study the low-lying coastal lands along the Nile Delta. However, it is concluded from geological data and geomorphologic aspects that Bardawil Lake is of a tectonic origin; it was much deeper than it is currently, and has been filled with sediments mostly since the Flandrian transgression (∼8–6 ka bp.

  10. Hydrochemical and toxicological characteristics of state national nature park “Kolsay Kolderi" lakes (Kungei Alatau, South-Eastern Kazakhstan

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    Krupa Elena G.

    2016-05-01

    Full Text Available In August 2015 four ultrafresh mountain lakes of Kolsay National Nature Park, located at an altitude of 1829–3170 m a.s.l., were examined. The water mineralization of the lakes decreased from 123.9 to 26.6 mg/dm3 with decreasing altitude above sea level. The concentration of dissolved organic matter and nitrogen compounds was at levels below the temporary maximum allowable concentration (MAC. Phosphorus has not been found in the water. The concentration of iron in the water has reached 44.0–440.0 g/dm3. The concentration of heavy metals in the water, except copper, was 10–100 times lower than the maximum allowable concentrations for standards of fishery waterbodies. The concentration of copper in water exceeded the permissible limits 2.6–5.5 times. The concentration of lead, copper, zinc, nickel and chromium in water has decreased from Lower Kolsay to Upper Kolsay. The most highland and shallow lake, which located under the Sarybulak mountain pass, had a higher concentration of lead, copper, zinc and nickel in the water than in the downstream lakes. The concentration of zinc, cadmium, lead, chromium, cobalt and nickel in the water of the other high mountain reservoirs of South-Eastern Kazakhstan has not exceeded 0.7 of MAC temporary. The concentration of copper has reached 1.5–13.9 of MAC temporary. In mountain lakes and reservoirs, the metal concentrations in the water decreased at lower altitudes, similar but less pronounce to their spatial dynamics in mountain rivers. Background concentration of cadmium and zinc in the mountain reservoirs of South-Eastern Kazakhstan was equivalent to the uncontaminated waters of the Tien Shan, the Alps and the Western Sayan mountain ranges. However, the concentration of copper, lead and chromium were higher respectively. Considering the remoteness of the region from the sources of anthropogenic influences, the background concentrations of heavy metals for water reservoirs of South-Eastern Kazakhstan

  11. Microplastic pollution in lakes and lake shoreline sediments - A case study on Lake Bolsena and Lake Chiusi (central Italy).

    Science.gov (United States)

    Fischer, Elke Kerstin; Paglialonga, Lisa; Czech, Elisa; Tamminga, Matthias

    2016-06-01

    Rivers and effluents have been identified as major pathways for microplastics of terrestrial sources. Moreover, lakes of different dimensions and even in remote locations contain microplastics in striking abundances. This study investigates concentrations of microplastic particles at two lakes in central Italy (Lake Bolsena, Lake Chiusi). A total number of six Manta Trawls have been carried out, two of them one day after heavy winds occurred on Lake Bolsena showing effects on particle distribution of fragments and fibers of varying size categories. Additionally, 36 sediment samples from lakeshores were analyzed for microplastic content. In the surface waters 2.68 to 3.36 particles/m(3) (Lake Chiusi) and 0.82 to 4.42 particles/m(3) (Lake Bolsena) were detected, respectively. Main differences between the lakes are attributed to lake characteristics such as surface and catchment area, depth and the presence of local wind patterns and tide range at Lake Bolsena. An event of heavy winds and moderate rainfall prior to one sampling led to an increase of concentrations at Lake Bolsena which is most probable related to lateral land-based and sewage effluent inputs. The abundances of microplastic particles in sediments vary from mean values of 112 (Lake Bolsena) to 234 particles/kg dry weight (Lake Chiusi). Lake Chiusi results reveal elevated fiber concentrations compared to those of Lake Bolsena what might be a result of higher organic content and a shift in grain size distribution towards the silt and clay fraction at the shallow and highly eutrophic Lake Chiusi. The distribution of particles along different beach levels revealed no significant differences. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Using satellite remote sensing to model and map the distribution of Bicknell's thrush (Catharus bicknelli) in the White Mountains of New Hampshire

    Science.gov (United States)

    Hale, Stephen Roy

    Landsat-7 Enhanced Thematic Mapper satellite imagery was used to model Bicknell's Thrush (Catharus bicknelli) distribution in the White Mountains of New Hampshire. The proof-of-concept was established for using satellite imagery in species-habitat modeling, where for the first time imagery spectral features were used to estimate a species-habitat model variable. The model predicted rising probabilities of thrush presence with decreasing dominant vegetation height, increasing elevation, and decreasing distance to nearest Fir Sapling cover type. To solve the model at all locations required regressor estimates at every pixel, which were not available for the dominant vegetation height and elevation variables. Topographically normalized imagery features Normalized Difference Vegetation Index and Band 1 (blue) were used to estimate dominant vegetation height using multiple linear regression; and a Digital Elevation Model was used to estimate elevation. Distance to nearest Fir Sapling cover type was obtained for each pixel from a land cover map specifically constructed for this project. The Bicknell's Thrush habitat model was derived using logistic regression, which produced the probability of detecting a singing male based on the pattern of model covariates. Model validation using Bicknell's Thrush data not used in model calibration, revealed that the model accurately estimated thrush presence at probabilities ranging from 0 to account for more total individuals and reproductive output than higher density less abundant land area. Efforts to conserve areas of highest individual density under the assumption that density reflects habitat quality could target the smallest fraction of the total population.

  13. A 10-Year Assessment of Hemlock Decline in the Catskill Mountain Region of New York State Using Hyperspectral Remote Sensing Techniques.

    Science.gov (United States)

    Hanavan, Ryan P; Pontius, Jennifer; Hallett, Richard

    2015-02-01

    The hemlock woolly adelgid is a serious pest of Eastern and Carolina hemlock in the eastern United States. Successfully managing the hemlock resource in the region depends on careful monitoring of the spread of this invasive pest and the targeted application of management options such as biological control, chemical, or silvicultural treatments. To inform these management activities and test the applicability of a landscape-scale remote sensing effort to monitor hemlock condition, hyperspectral collections, and concurrent ground-truthing in 2001 and 2012 of hemlock condition were compared with field metrics spanning a 10-yr survey in the Catskills region of New York. Fine twig dieback significantly increased from 9 to 15% and live crown ratio significantly decreased from 67 to 56% in 2001 and 2012, respectively. We found a significant shift from 59% "healthy" hemlock in 2001 to only 16% in 2012. However, this shift from healthy to declining classifications was mostly a shift to decline class 2 "early decline". These results indicate that while there has been significant increase in decline symptoms as measured in both field and remote sensing assessments, a majority of the declining areas identified in the resulting spatial coverages remain in the "early decline" category and widespread mortality has not yet occurred. While this slow decline across the region stands in contrast to many reports of mortality within 10 yr, the results from this work are in line with other long-term monitoring studies and indicate that armed with the spatial information provided here, continued management strategies can be focused on particular areas to help control the further decline of hemlock in the region. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

  14. AN ECOLOGICAL ASSESSMENT OF INVASIVE AND AGRESSIVE PLANT SPECIES IN COASTAL WETLANDS OF THE LAURENTIAN GREAT LAKES: A COMBINED FIELD BASED AND REMOTE SENSING APPROACH

    Science.gov (United States)

    The aquatic plant communities within coastal wetlands of the Laurentian Great Lakes are among the most biologically diverse and productive systems of the world. Coastal wetlands have been especially impacted by landscape conversion and have undergone a marked decline in plant com...

  15. Cogs in the endless machine: lakes, climate change and nutrient cycles: a review.

    Science.gov (United States)

    Moss, Brian

    2012-09-15

    Lakes have, rather grandly, been described as sentinels, integrators and regulators of climate change (Williamson et al., Limnol. Oceanogr. 2009; 54: 2273-82). Lakes are also part of the continuum of the water cycle, cogs in a machine that processes water and elements dissolved and suspended in myriad forms. Assessing the changes in the functioning of the cogs and the machine with respect to these substances as climate changes is clearly important, but difficult. Many other human-induced influences, not least eutrophication, that impact on catchment areas and consequently on lakes, have generally complicated the recording of recent change in sediment records and modern sets of data. The least confounded evidence comes from remote lakes in mountain and polar regions and suggests effects of warming that include mobilisation of ions and increased amounts of phosphorus. A cottage industry has arisen in deduction and prediction of the future effects of climate change on lakes, but the results are very general and precision is marred not only by confounding influences but by the complexity of the lake system and the infinite variety of possible future scenarios. A common conclusion, however, is that warming will increase the intensity of symptoms of eutrophication. Direct experimentation, though expensive and still unusual and confined to shallow lake and wetland systems is perhaps the most reliable approach. Results suggest increased symptoms of eutrophication, and changes in ecosystem structure, but in some respects are different from those deduced from comparisons along latitudinal gradients or by inference from knowledge of lake behaviour. Experiments have shown marked increases in community respiration compared with gross photosynthesis in mesocosm systems and it may be that the most significant churnings of these cogs in the earth-air-water machine will be in their influence on the carbon cycle, with possibly large positive feedback effects on warming. Copyright

  16. Environmental evidence of fossil fuel pollution in Laguna Chica de San Pedro lake sediments (Central Chile)

    Energy Technology Data Exchange (ETDEWEB)

    Chirinos, L. [Centro de Ciencias Ambientales EULA-Chile, Universidad de Concepcion, PO Box 160-C, Concepcion (Chile)]. E-mail: lchirin@pucp.edu.pe; Rose, N.L. [Environmental Change Research Centre, University College London, 26 Bedford Way, London WG1HOAP (United Kingdom); Urrutia, R. [Centro de Ciencias Ambientales EULA-Chile, Universidad de Concepcion, PO Box 160-C, Concepcion (Chile); Munoz, P. [Departamento de Biologia Marina, Universidad Catolica del Norte, Larrondo 1281, Coquimbo (Chile); Torrejon, F. [Centro de Ciencias Ambientales EULA-Chile, Universidad de Concepcion, PO Box 160-C, Concepcion (Chile); Torres, L. [Departamento de Botanica, Universidad de Concepcion, Concepcion (Chile); Cruces, F. [Departamento de Botanica, Universidad de Concepcion, Concepcion (Chile); Araneda, A. [Centro de Ciencias Ambientales EULA-Chile, Universidad de Concepcion, PO Box 160-C, Concepcion (Chile); Zaror, C. [Facultad de Ingenieria Quimica, Universidad de Concepcion, Concepcion (Chile)

    2006-05-15

    This paper describes lake sediment spheroidal carbonaceous particle (SCP) profiles from Laguna Chica San Pedro, located in the Biobio Region, Chile (36{sup o} 51' S, 73{sup o} 05' W). The earliest presence of SCPs was found at 16 cm depth, corresponding to the 1915-1937 period, at the very onset of industrial activities in the study area. No SCPs were found at lower depths. SCP concentrations in Laguna Chica San Pedro lake sediments were directly related to local industrial activities. Moreover, no SCPs were found in Galletue lake (38{sup o} 41' S, 71{sup o} 17.5' W), a pristine high mountain water body used here as a reference site, suggesting that contribution from long distance atmospheric transport could be neglected, unlike published data from remote Northern Hemisphere lakes. These results are the first SCP sediment profiles from Chile, showing a direct relationship with fossil fuel consumption in the region. Cores were dated using the {sup 21}Pb technique. - The lake sediment record of SCPs shows the record of fossil-fuel derived pollution in Central Chile.

  17. Environmental evidence of fossil fuel pollution in Laguna Chica de San Pedro lake sediments (Central Chile)

    International Nuclear Information System (INIS)

    Chirinos, L.; Rose, N.L.; Urrutia, R.; Munoz, P.; Torrejon, F.; Torres, L.; Cruces, F.; Araneda, A.; Zaror, C.

    2006-01-01

    This paper describes lake sediment spheroidal carbonaceous particle (SCP) profiles from Laguna Chica San Pedro, located in the Biobio Region, Chile (36 o 51' S, 73 o 05' W). The earliest presence of SCPs was found at 16 cm depth, corresponding to the 1915-1937 period, at the very onset of industrial activities in the study area. No SCPs were found at lower depths. SCP concentrations in Laguna Chica San Pedro lake sediments were directly related to local industrial activities. Moreover, no SCPs were found in Galletue lake (38 o 41' S, 71 o 17.5' W), a pristine high mountain water body used here as a reference site, suggesting that contribution from long distance atmospheric transport could be neglected, unlike published data from remote Northern Hemisphere lakes. These results are the first SCP sediment profiles from Chile, showing a direct relationship with fossil fuel consumption in the region. Cores were dated using the 21 Pb technique. - The lake sediment record of SCPs shows the record of fossil-fuel derived pollution in Central Chile

  18. Les vagues dans les retenues d’altitudes : analyse et méthodes pour la prévention Water waves in mountainous lakes: analysis and methods for prevention

    Directory of Open Access Journals (Sweden)

    Mohamed Naaim, Gérard Degoutte et François Delorme

    2010-09-01

    Full Text Available Édifiées dans les stations de loisirs de montagne pour la production de neige de culture, les retenues d'altitude, comme tout ouvrage hydraulique, sont soumises aux aléas météorologiques qui peuvent générer des risques pour la sécurité publique. Les auteurs s'intéressent ici aux conséquences des vagues provoquées par le vent et les mouvements gravitaires rapides sur de tels ouvrages et étudient les moyens de protection à mettre en place.The load of the wind and the impact of rapid mass movements in a reservoir generate waves whose nature and properties depend on the magnitude of the load and the water depth in the reservoir. In this paper we summarized the main existing scaling laws allowing assessing the resulting hydrodynamic effects, focusing not only on the amplitude of the waves, but also on its nature. The wind and the slow movements produce sinusoidal waves while rapid mass movements produce steeper water waves such as tsunamis. Given the limited extension of the mountain lakes, the produced water waves rapidly meet the shores or the dam on which they generate a run-up whose amplitude depends on the characteristics of the incident wave and the slope of the shore. We have undertaken a theoretical analysis and collected several experimental data in order to show the similarities and the differences between the sinusoidal waves and the solitary waves in terms of run-up. We finally, choose simple formulas and produced a chart enabling any engineer to make a first diagnosis.

  19. Mountaineering Tourism

    Directory of Open Access Journals (Sweden)

    Patrick Maher

    2016-08-01

    Full Text Available Reviewed: Mountaineering Tourism Edited by Ghazali Musa, James Higham, and Anna Thompson-Carr. Abingdon, United Kingdom: Routledge, 2015. xxvi + 358 pp. Hardcover. US$ 145.00. ISBN 978-1-138-78237-2.

  20. Linking Land Use Changes to Surface Water Quality Variability in Lake Victoria: Some Insights From Remote Sensing (GC41B-1101)

    Science.gov (United States)

    Limaye, Ashutosh; Mugo, Robinson; Wanjohi, James; Farah, Hussein; Wahome, Anastasia; Flores, Africa; Irwin, Dan

    2016-01-01

    Various land use changes driven by urbanization, conversion of grasslands and woodlands into farmlands, intensification of agricultural practices, deforestation, land fragmentation and degradation are taking place in Africa. In Kenya, agriculture is the main driver of land use conversions. The impacts of these land use changes are observable in land cover maps, and eventually in the hydrological systems. Reduction or change of natural vegetation cover types increases the speed of surface runoff and reduces water and nutrient retention capacities. This can lead to high nutrient inputs into lakes, resulting in eutrophication, siltation and infestation of floating aquatic vegetation. To assess if changes in land use could be contributing to increased phytoplankton blooms and sediment loads into Lake Victoria, we analyzed land use land cover data from Landsat, as well as surface chlorophyll-a and total suspended matter from MODIS-Aqua sensor.

  1. Regional-scale GIS-models for assessment of hazards from glacier lake outbursts: evaluation and application in the Swiss Alps

    Directory of Open Access Journals (Sweden)

    C. Huggel

    2003-01-01

    Full Text Available Debris flows triggered by glacier lake outbursts have repeatedly caused disasters in various high-mountain regions of the world. Accelerated change of glacial and periglacial environments due to atmospheric warming and increased anthropogenic development in most of these areas raise the need for an adequate hazard assessment and corresponding modelling. The purpose of this paper is to pro-vide a modelling approach which takes into account the current evolution of the glacial environment and satisfies a robust first-order assessment of hazards from glacier-lake outbursts. Two topography-based GIS-models simulating debris flows related to outbursts from glacier lakes are presented and applied for two lake outburst events in the southern Swiss Alps. The models are based on information about glacier lakes derived from remote sensing data, and on digital elevation models (DEM. Hydrological flow routing is used to simulate the debris flow resulting from the lake outburst. Thereby, a multiple- and a single-flow-direction approach are applied. Debris-flow propagation is given in probability-related values indicating the hazard potential of a certain location. The debris flow runout distance is calculated on the basis of empirical data on average slope trajectory. The results show that the multiple-flow-direction approach generally yields a more detailed propagation. The single-flow-direction approach, however, is more robust against DEM artifacts and, hence, more suited for process automation. The model is tested with three differently generated DEMs (including aero-photogrammetry- and satellite image-derived. Potential application of the respective DEMs is discussed with a special focus on satellite-derived DEMs for use in remote high-mountain areas.

  2. Teaching wilderness first aid in a remote First Nations community: the story of the Sachigo Lake Wilderness Emergency Response Education Initiative.

    Science.gov (United States)

    Born, Karen; Orkin, Aaron; VanderBurgh, David; Beardy, Jackson

    2012-01-01

    To understand how community members of a remote First Nations community respond to an emergency first aid education programme. A qualitative study involving focus groups and participant observation as part of a community-based participatory research project, which involved the development and implementation of a wilderness first aid course in collaboration with the community. Twenty community members participated in the course and agreed to be part of the research focus groups. Three community research partners validated and reviewed the data collected from this process. These data were coded and analysed using open coding. Community members responded to the course in ways related to their past experiences with injury and first aid, both as individuals and as members of the community. Feelings of confidence and self-efficacy related access to care and treatment of injury surfaced during the course. Findings also highlighted how the context of the remote First Nations community influenced the delivery and development of course materials. Developing and delivering a first aid course in a remote community requires sensitivity towards the response of participants to the course, as well as the context in which it is being delivered. Employing collaborative approaches to teaching first aid can aim to address these unique needs. Though delivery of a first response training programme in a small remote community will probably not impact the morbidity and mortality associated with injury, it has the potential to impact community self-efficacy and confidence when responding to an emergency situation.

  3. Geochemistry, water balance, and stable isotopes of a “clean” pit lake at an abandoned tungsten mine, Montana, USA

    International Nuclear Information System (INIS)

    Gammons, Christopher H.; Pape, Barbara L.; Parker, Stephen R.; Poulson, Simon R.; Blank, Carrine E.

    2013-01-01

    Highlights: • An abandoned open pit mine is now a 30 m deep lake with excellent water quality. • Concentrations of sulfate, nutrients, and most trace metals are extremely low. • Based on water isotopes, the lake is 30% evaporated with a 2.5 yr residence time. • Stable isotopes of DIC and DO track in-lake bio-geochemical processes. • Phytoplankton are active at depths as great as 20 m. - Abstract: The Calvert Mine is a small tungsten-rich (scheelite) skarn deposit in a remote, mountainous region of southwest Montana, USA. The open-pit mine closed in the 1970s and subsequently flooded to form a pit lake that is roughly conical in shape, 30 m deep and 120 m in diameter, with no surface inlet or outlet. The lake is holomictic with a groundwater flow-through hydrology and an estimated residence time of 2.5–5 y. Water isotopes show that the lake is at an approximate steady state with respect to water balance and has experienced 30% evaporation. The lake has a near-neutral pH, exceptional clarity, and extremely low concentrations of nutrients, sulfate, and most metals, including tungsten. Manganese concentrations are slightly elevated and increase with depth towards the sediment–water interface. Despite seasonally anoxic conditions in the deep water, dissolved Fe concentrations are orders of magnitude lower than Mn, suggesting that insufficient organic carbon is present in the sediment of this oligotrophic lake to drive bacterial Fe reduction. Based on stable isotope fingerprinting, diffuse seepage that enters a nearby headwater stream at the base of a large waste-rock pile can be directly linked to the partially evaporated pit lake. However, this seepage has neutral pH and low metal concentrations, and poses no threats to the environment. Stable isotopes of dissolved inorganic carbon (DIC) and dissolved oxygen (DO) are used to track the relative importance of photosynthesis and respiration with depth. In summer, a zone of high productivity exists near the

  4. Classification of High-Mountain Vegetation Communities within a Diverse Giant Mountains Ecosystem Using Airborne APEX Hyperspectral Imagery

    Directory of Open Access Journals (Sweden)

    Adriana Marcinkowska-Ochtyra

    2018-04-01

    Full Text Available Mapping plant communities is a difficult and time consuming endeavor. Methods relying on field surveys deliver high quality data but are usually limited to relatively small areas. In this paper we apply airborne hyperspectral data to vegetation mapping in remote and hard to reach areas. We classified 22 vegetation communities in the Giant Mountains on 3.12-m Airborne Prism Experiment (APEX hyperspectral images, registered in 288 spectral bands (10 September 2012. As the classification algorithm, Support Vector Machines (SVM was used. APEX data were corrected geometrically and atmospherically, and three dimensionality reduction methods were performed to select the best dataset. As reference we used a non-forest vegetation map containing vegetation communities of Polish Karkonosze National Park from 2002, orthophotomap and field surveys data from 2013 to 2014. We obtained the post-classification maps of 22 vegetation communities, lakes and areas without any vegetation. Iterative accuracy assessment repeated 100 times was used to obtain the most objective results for individual communities. The median value of overall accuracy (OA was 84%. Fourteen out of twenty-four classes were classified of more than 80% of producer accuracy (PA and sixteen out of twenty-four of user accuracy (UA. APEX data and SVM with the use of iterative accuracy assessment are useful for the mountain communities classification. This can support both Polish and Czech national parks management by giving the information about diversity of communities in the whole transboundary area, helping with identification especially in changing environment caused by humans.

  5. 77 FR 8895 - Jimbilnan, Pinto Valley, Black Canyon, Eldorado, Ireteba Peaks, Nellis Wash, Spirit Mountain, and...

    Science.gov (United States)

    2012-02-15

    ..., Pinto Valley, Black Canyon, Eldorado, Ireteba Peaks, Nellis Wash, Spirit Mountain, and Bridge Canyon..., Eldorado, Ireteba Peaks, Nellis Wash, Spirit Mountain, and Bridge Canyon Wilderness Areas, Lake Mead... wilderness character; providing for reasonable use of Spirit Mountain and adjacent areas in a manner meeting...

  6. Teaching wilderness first aid in a remote First Nations community: the story of the Sachigo Lake Wilderness Emergency Response Education Initiative

    OpenAIRE

    Karen Born; Aaron Orkin; David VanderBurgh; Jackson Beardy

    2012-01-01

    Objective. To understand how community members of a remote First Nations community respond to an emergency first aid education programme. Study design. A qualitative study involving focus groups and participant observation as part of a communitybased participatory research project, which involved the development and implementation of a wilderness first aid course in collaboration with the community. Methods. Twenty community members participated in the course and agreed to be part of the rese...

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

    Science.gov (United States)

    Hook, Simon J.

    2008-01-01

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

  8. The dynamics the quantitative changes of mycoflora in two lakes differing in trophicity (Poland. I.

    Directory of Open Access Journals (Sweden)

    Teresa Korniłłowicz

    2014-08-01

    Full Text Available It was demonstrated that the number of saprophytic fungi in the population of plankton in mesotrophic lake changing to eutrophic (Lake Piaseczno was mountained a similiar level (average values as in the eutrophic one (Lake Głębokie. The seasonal and annual changes in the number of fungi in the waters of the lake with lower trophicity were markedly stronger than those in the lake with higher trophicity. In the mesotrophic lake this was connected with the intensity of phytoplankton development. The greatest accumulation of fungi occured in the waters of littoral zone in both lakes and in the pelagial metha- and hypolimniun of the Lake Piaseczno.

  9. IMPACT OF THE ATATÜRK DAM LAKE ON AGRO-METEOROLOGICAL ASPECTS OF THE SOUTHEASTERN ANATOLIA REGION USING REMOTE SENSING AND GIS ANALYSIS

    Directory of Open Access Journals (Sweden)

    O. Ozcan

    2012-07-01

    Full Text Available The Atatürk Dam is the fourth largest clay-cored rock fill dam in the world. It was constructed on the Euphrates River located in semi-arid Southeastern Turkey in the 1980s as the central component of a large-scale regional development project for the Southeastern Anatolia region (referred to as GAP. The construction began in 1983 and was completed in 1990. The dam and the hydroelectric power plant, which went into service after filling up the reservoir was accomplished in 1992. The Atatürk Dam, which has a height of 169 m, a total storage capacity of 48.7 million m3, and a surface area of about 817 km2 plays an important role in the development of Turkey's energy and agriculture sectors. In this study, the spatial and temporal impacts of the Atatürk Dam on agro-meteorological aspects of the Southeastern Anatolia region have been investigated. Change detection and environmental impacts due to water-reserve changes in Atatürk Dam Lake have been determined and evaluated using multi-temporal Landsat satellite imageries and meteorological datasets within a period of 1984 to 2011. These time series have been evaluated for three time periods. Dam construction period constitutes the first part of the study. Land cover/use changes especially on agricultural fields under the Atatürk Dam Lake and its vicinity have been identified between the periods of 1984 to 1992. The second period comprises the 10-year period after the completion of filling up the reservoir in 1992. At this period, Landsat and meteorological time-series analyses are examined to assess the impact of the Atatürk Dam Lake on selected irrigated agricultural areas. For the last 9-year period from 2002 to 2011, the relationships between seasonal water-reserve changes and irrigated plains under changing climatic factors primarily driving vegetation activity (monthly, seasonal, and annual fluctuations of rainfall rate, air temperature, humidity on the watershed have been investigated

  10. Drivers of Holocene treeline and timberline changes in the Retezat Mountains (South Carpathians, Romania

    Directory of Open Access Journals (Sweden)

    Ildiko VINCZE

    2014-11-01

    Full Text Available Four high-altitude lake sediment sequences (Lake Brazi, 1740 m .as.l., Lake Gales 1990 m a.s.l., Lake Bucura, 2040 m a.s.l. and Lake Lia, 1910 m a.s.l. were analyzed using multi-proxy methods (pollen, stomata, plant macrofossil and micro- and macrocharcoal in order to study responses of treeline and alpine/subalpine vegetation to climate change and human impact during the last 15000 years. Observing and reconstructing the changes of the position and structure of the treeline can provide valuable information on biotic and other factors such as human activities. Sediment cores were taken from two lakes on the northern slope (Lake Brazi and Lake Gales and two lakes from the southern slope (Lake Lia and Lake Bucura in the Retezat Mountains, South Carpathians (Romania.

  11. The importance of geomorphic and hydrologic factors in shaping the sensitivity of alpine/subalpine lake volumes to shifts in climate

    Science.gov (United States)

    Mercer, J.; Liefert, D. T.; Shuman, B. N.; Befus, K. M.; Williams, D. G.; Kraushaar, B.

    2017-12-01

    Alpine and subalpine lakes are important components of the hydrologic cycle in mountain ecosystems. These lakes are also highly sensitive to small shifts in temperature and precipitation. Mountain lake volumes and their contributions to mountain hydrology may change in response to even minor declines in snowpack or increases in temperature. However, it is still not clear to what degree non-climatic factors, such as geomorphic setting and lake geometry, play in shaping the sensitivity of high elevation lakes to climate change. We investigated the importance of lake geometry and groundwater connectivity to mountain lakes in the Snowy Range, Wyoming using a combination of hydrophysical and hydrochemical methods, including stable water isotopes, to better understand the role these factors play in controlling lake volume. Water isotope values in open lakes were less sensitive to evaporation compared to those in closed basin lakes. Lake geometry played an important role, with wider, shallower lakes being more sensitive to evaporation over time. Groundwater contributions appear to play only a minor role in buffering volumetric changes to lakes over the growing season. These results confirm that mountain lakes are sensitive to climate factors, but also highlight a significant amount of variability in that sensitivity. This research has implications for water resource managers concerned with downstream water quantity and quality from mountain ecosystems, biologists interested in maintaining aquatic biodiversity, and paleoclimatologists interested in using lake sedimentary information to infer past climate regimes.

  12. Impact of land use changes on hydrology of Mt. Kilimanjaro. The case of Lake Jipe catchment

    Science.gov (United States)

    Ngugi, Keziah; Ogindo, Harun; Ertsen, Maurits

    2015-04-01

    Mt. Kilimanjaro is an important water tower in Kenya and Tanzania. Land degradation and land use changes have contributed to dwindling surface water resources around Mt. Kilimanjaro. This study focuses on Lake Jipe catchment of about 451Km2 (Ndetei 2011) which is mainly drained by River Lumi, a tributary of river Pangani. River Lumi starts from Mt. Kilimanjaro and flows North east wards to cross the border from Tanzania to Kenya eventually flowing into Lake Jipe which is a trans-boundary lake. The main purpose of this study was to investigate historical land use changes and relate this to reduction in surface water resources. The study will propose measures that could restore the catchment thereby enhancing surface water resources feeding Lake Jipe. A survey was conducted to document community perspectives of historical land use changes. This information was corroborated using Landsat remote sensed images spanning the period 1985-2013 to determine changes in the land cover due to human activities on Lake Jipe Catchment. River Lumi flow data was obtained from Water Resources Management Authority and analyzed for flow trends. The dwindling extent of the Lake was obtained from the community's perspective survey and by Landsat images. Community survey and remote sensing indicated clearing of the forest on the mountain and conversion of the same to crop production fields; damming of river Lumi in Tanzania, conversion of bush land to crop production fields further downstream of river Lumi and irrigation. There is heavy infestation of the invasive species Prosopis juliflora which had aggressively colonized grazing land and blocked irrigation canals. Other land use changes include land fragmentation due to subdivision. Insecure land tenure was blamed for failure by farmers to develop soil and water conservation infrastructure. Available River gauging data showed a general decline in river flow. Heavy flooding occurred during rainy seasons. Towards Lake Jipe after the river

  13. LIMNOLOGY, LAKE BASINS, LAKE WATERS

    Directory of Open Access Journals (Sweden)

    Petre GÂŞTESCU

    2009-06-01

    Full Text Available Limnology is a border discipline between geography, hydrology and biology, and is also closely connected with other sciences, from it borrows research methods. Physical limnology (the geography of lakes, studies lake biotopes, and biological limnology (the biology of lakes, studies lake biocoenoses. The father of limnology is the Swiss scientist F.A. Forel, the author of a three-volume entitled Le Leman: monographie limnologique (1892-1904, which focuses on the geology physics, chemistry and biology of lakes. He was also author of the first textbook of limnology, Handbuch der Seenkunde: allgemeine Limnologie,(1901. Since both the lake biotope and its biohydrocoenosis make up a single whole, the lake and lakes, respectively, represent the most typical systems in nature. They could be called limnosystems (lacustrine ecosystems, a microcosm in itself, as the American biologist St.A. Forbes put it (1887.

  14. Changes in aquatic insect emergence in response to whole-lake experimental manipulations of introduced trout

    Science.gov (United States)

    Karen L. Pope; Jonah Piovia-Scott; Sharon P. Lawler

    2009-01-01

    1. Insects emerging from mountain lakes provide an important food source for many terrestrial predators. The amount of insect subsidy that emerges from lakes is influenced by predator composition, but predator effects could be ameliorated by greater habitat complexity. We conducted a replicated whole-lake experiment to test the effects of introduced fish...

  15. Air pollution: worldwide effects on mountain forests

    Science.gov (United States)

    Anne M. Rosenthal; Andrzej Featured: Bytnerowicz

    2004-01-01

    Widespread forest decline in remote areas of the Carpathian Mountains has been linked to air pollution from urban and industrial regions. Besides injuring plant tissues directly, pollutants may deposit to soils and water, drastically changing susceptible ecosystems. Researcher Andrzej Bytnerowicz has developed effective methods for assessing air quality over wildlands...

  16. Transient Tsunamis in Lakes

    Science.gov (United States)

    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

  17. Challenges in understanding, modelling, and mitigating Lake Outburst Flood Hazard: experiences from Central Asia

    Science.gov (United States)

    Mergili, Martin; Schneider, Demian; Andres, Norina; Worni, Raphael; Gruber, Fabian; Schneider, Jean F.

    2010-05-01

    Lake Outburst Floods can evolve from complex process chains like avalanches of rock or ice that produce flood waves in a lake which may overtop and eventually breach glacial, morainic, landslide, or artificial dams. Rising lake levels can lead to progressive incision and destabilization of a dam, to enhanced ground water flow (piping), or even to hydrostatic failure of ice dams which can cause sudden outflow of accumulated water. These events often have a highly destructive potential because a large amount of water is released in a short time, with a high capacity to erode loose debris, leading to a powerful debris flow with a long travel distance. The best-known example of a lake outburst flood is the Vajont event (Northern Italy, 1963), where a landslide rushed into an artificial lake which spilled over and caused a flood leading to almost 2000 fatalities. Hazards from the failure of landslide dams are often (not always) fairly manageable: most breaches occur in the first few days or weeks after the landslide event and the rapid construction of a spillway - though problematic - has solved some hazardous situations (e.g. in the case of Hattian landslide in 2005 in Pakistan). Older dams, like Usoi dam (Lake Sarez) in Tajikistan, are usually fairly stable, though landsildes into the lakes may create floodwaves overtopping and eventually weakening the dams. The analysis and the mitigation of glacial lake outburst flood (GLOF) hazard remains a challenge. A number of GLOFs resulting in fatalities and severe damage have occurred during the previous decades, particularly in the Himalayas and in the mountains of Central Asia (Pamir, Tien Shan). The source area is usually far away from the area of impact and events occur at very long intervals or as singularities, so that the population at risk is usually not prepared. Even though potentially hazardous lakes can be identified relatively easily with remote sensing and field work, modeling and predicting of GLOFs (and also

  18. Characterizing anthropogenic impacts on two mid-altitude Himalayan lakes in the Western Himalaya: A look at shifts in water chemistry and phytoplankton communities

    Science.gov (United States)

    Marcus, T. S.; Tiwari, S.; Bhatt, J. P.; Pandit, M. K.; Varner, R. K.

    2017-12-01

    The Himalayan region is globally regarded for its natural mountain ecosystems but increased agricultural expansion and urbanization have resulted in greater nutrient loading in Himalayan water bodies causing widespread fish kills and shrinking lakes. Despite concerns for environmental degradation, lack of empirical investigations and quantitative data are major constraints in understanding these events. To determine the impact of human development on Himalayan lakes, we investigated Rewalsar, a spring-fed lake and Kareri a glacial-fed lake in the state of Himachal Pradesh. Rewalsar is surrounded by a rapidly growing town and agricultural fields while Kareri Lake is situated in a relatively remote area. Measurements were made in the spring periods of 2013 and 2016. Water samples were collected 1m below the lake surface and analyzed for major ions, nitrates, phosphates, DO, pH, temperature, turbidity, and TDS. Alagal samples were collected from each lake and species counted and identified using standard taxonomic literature. Statistical analysis was performed using PC-ORD. Results showed a significant change in water chemistry and phytoplankton communities with Rewalsar Lake showing an increase in pollutant tolerant algae over the sample period. Principle component analysis showed that the 2016 data from Kareri Lake had phytoplankton communities and chemical data resembling the urban lake of Rewalsar. Kareri Lake had the highest DO (10 mg/ml) while Rewalsar showed the lowest DO at 3 mg/ml in 2016, a decrease from 8 mg/ml in 2013. With a total oxygen demand (TOD) of 6.5 mg/ml in Rewalsar, the decreasing DO value is likely the cause of the increasing annual fish kills as reported by local governments. TDS measurements were highest in Rewalsar Lake compared to the TDS levels of Kareri, indicating a higher amount of surface runoff from the surrounding area in Rewalsar. Nitrate and phosphate levels also increased over this time period. Our multi-year investigation also

  19. Research plan for integrated ecosystem and pollutant monitoring at remote wilderness study sites

    International Nuclear Information System (INIS)

    Bruns, D.A.; Wiersma, G.B.

    1988-03-01

    This research plan outlines an approach to the measurement of pollutants and ecosystem parameters at remote, high-elevation, wilderness study sites. A multimedia, systems approach to environmental monitoring is emphasized. The primary purpose of the research is to apply and field test a technical report entitled ''Guidelines for measuring the physical, chemical, and biological condition of wilderness ecosystems.'' This document intended to provide Federal Land Managers with information to establish environmental monitoring programs in wilderness areas. To date, this monitoring document has yet to be evaluated under rigorous field conditions at a remote, high-elevation Rocky Mountain site. For the purpose of field testing approaches to monitoring of pollutants and ecosystems in remote, wilderness areas, evaluation criteria were developed. These include useability, cost-effectiveness, data variability, alternative approaches, ecosystems conceptual approach, and quality assurance. Both the Forest Service and INEL environmental monitoring techniques will be evaluated with these criteria. Another objective of this research plan is to obtain an integrated data base on pollutants and ecosystem structure and function at a remote study site. The methods tested in this project will be used to acquire these data from a systems approach. This includes multimedia monitoring of air and water quality, soils, and forest, stream, and lake ecosystems. 71 refs., 1 fig., 9 tabs

  20. Cogs in the endless machine: Lakes, climate change and nutrient cycles: A review

    Energy Technology Data Exchange (ETDEWEB)

    Moss, Brian, E-mail: brmoss@liverpool.ac.uk

    2012-09-15

    Lakes have, rather grandly, been described as sentinels, integrators and regulators of climate change (). Lakes are also part of the continuum of the water cycle, cogs in a machine that processes water and elements dissolved and suspended in myriad forms. Assessing the changes in the functioning of the cogs and the machine with respect to these substances as climate changes is clearly important, but difficult. Many other human-induced influences, not least eutrophication, that impact on catchment areas and consequently on lakes, have generally complicated the recording of recent change in sediment records and modern sets of data. The least confounded evidence comes from remote lakes in mountain and polar regions and suggests effects of warming that include mobilisation of ions and increased amounts of phosphorus. A cottage industry has arisen in deduction and prediction of the future effects of climate change on lakes, but the results are very general and precision is marred not only by confounding influences but by the complexity of the lake system and the infinite variety of possible future scenarios. A common conclusion, however, is that warming will increase the intensity of symptoms of eutrophication. Direct experimentation, though expensive and still unusual and confined to shallow lake and wetland systems is perhaps the most reliable approach. Results suggest increased symptoms of eutrophication, and changes in ecosystem structure, but in some respects are different from those deduced from comparisons along latitudinal gradients or by inference from knowledge of lake behaviour. Experiments have shown marked increases in community respiration compared with gross photosynthesis in mesocosm systems and it may be that the most significant churnings of these cogs in the earth-air-water machine will be in their influence on the carbon cycle, with possibly large positive feedback effects on warming. -- Highlights: Black-Right-Pointing-Pointer Climate change has had

  1. Assessing the effects of climate and volcanism on diatom and chironomid assemblages in an Andean lake near Quito, Ecuador

    Directory of Open Access Journals (Sweden)

    Neal Michelutti

    2015-12-01

    Full Text Available The tropical Andes are undergoing climate changes that rival those occurring anywhere else on the planet, and are likely to have profound consequences for ecosystems. Paleolimnological investigations of remote mountain lakes can provide details of past environmental change, especially where monitoring data are absent. Here, we reconstruct fossil diatom and chironomid communities spanning the last several hundred years from an Andean lake located in an ecological reserve near Quito, Ecuador. Both diatoms and chironomids recorded assemblage shifts reflective of changing climate conditions. The diatoms are likely responding primarily to temperature-related limnological changes, recording an increase in the number of planktonic taxa in the most recent sediments. This change is consistent with warmer conditions that result in enhanced periods of thermal stratification, allowing planktonic species to proliferate. The chironomids appear to respond mainly to a change in precipitation regime, recording a greater number of terrestrial and semi-terrestrial taxa that have been transported to the lake. A thick tephra deposit at the base of the sediment core affected both diatom and chironomid assemblages. The diatoms registered a change in species composition highlighting the ability of certain taxa to rapidly colonize new environments. In contrast, the chironomids showed a marked drop in abundance immediately following the tephra, but no change in species composition. In both cases the ecological response was short-lived, illustrating the resiliency of the lake to return to baseline conditions following volcanic inputs.

  2. Remote RemoteRemoteRemote sensing potential for sensing ...

    African Journals Online (AJOL)

    Remote RemoteRemoteRemote sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing p. A Ngie, F Ahmed, K Abutaleb ...

  3. NPDES Permit for Rocky Mountain Arsenal Recycled Water Pipeline in Colorado

    Science.gov (United States)

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

  4. Investigation of landscape and lake acidification relationships

    Energy Technology Data Exchange (ETDEWEB)

    Rush, R.M.; Honea, R.B.; Krug, E.C.; Peplies, R.W.; Dobson, J.E.; Baxter, F.P.

    1985-10-01

    This interim report presents the rationale and initial results for a program designed to gather and analyze information essential to a better understanding of lake acidification in the northeastern United States. The literature pertinent to a study of landscape and lake acidification relationships is reviewed and presented as the rationale for a landscape/lake acidification study. The results of a study of Emmons Pond in northwestern Connecticut are described and lead to the conclusion that a landscape change was a contributor to the acidification of this pond. A regional study of sixteen lakes in southern New England using Landsat imagery is described, and preliminary observations from a similar study in the Adirondack Mountains are given. These results indicate that satellite imagery can be useful in identifying types of ground cover important to landscape/lake acidification relationships.

  5. Contaminant Monitoring Strategy for Henrys Lake, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    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

  6. Predicting future glacial lakes in Austria using different modelling approaches

    Science.gov (United States)

    Otto, Jan-Christoph; Helfricht, Kay; Prasicek, Günther; Buckel, Johannes; Keuschnig, Markus

    2017-04-01

    Glacier retreat is one of the most apparent consequences of temperature rise in the 20th and 21th centuries in the European Alps. In Austria, more than 240 new lakes have formed in glacier forefields since the Little Ice Age. A similar signal is reported from many mountain areas worldwide. Glacial lakes can constitute important environmental and socio-economic impacts on high mountain systems including water resource management, sediment delivery, natural hazards, energy production and tourism. Their development significantly modifies the landscape configuration and visual appearance of high mountain areas. Knowledge on the location, number and extent of these future lakes can be used to assess potential impacts on high mountain geo-ecosystems and upland-lowland interactions. Information on new lakes is critical to appraise emerging threads and potentials for society. The recent development of regional ice thickness models and their combination with high resolution glacier surface data allows predicting the topography below current glaciers by subtracting ice thickness from glacier surface. Analyzing these modelled glacier bed surfaces reveals overdeepenings that represent potential locations for future lakes. In order to predict the location of future glacial lakes below recent glaciers in the Austrian Alps we apply different ice thickness models using high resolution terrain data and glacier outlines. The results are compared and validated with ice thickness data from geophysical surveys. Additionally, we run the models on three different glacier extents provided by the Austrian Glacier Inventories from 1969, 1998 and 2006. Results of this historical glacier extent modelling are compared to existing glacier lakes and discussed focusing on geomorphological impacts on lake evolution. We discuss model performance and observed differences in the results in order to assess the approach for a realistic prediction of future lake locations. The presentation delivers

  7. Potentially dangerous glacial lakes in Kyrgyzstan - Research overview of 2004-2015

    Science.gov (United States)

    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.

  8. Remote Research

    CERN Document Server

    Tulathimutte, Tony

    2011-01-01

    Remote studies allow you to recruit subjects quickly, cheaply, and immediately, and give you the opportunity to observe users as they behave naturally in their own environment. In Remote Research, Nate Bolt and Tony Tulathimutte teach you how to design and conduct remote research studies, top to bottom, with little more than a phone and a laptop.

  9. Lake Cadagno

    DEFF Research Database (Denmark)

    Tonolla, Mauro; Storelli, Nicola; Danza, Francesco

    2017-01-01

    Lake Cadagno (26 ha) is a crenogenic meromictic lake located in the Swiss Alps at 1921 m asl with a maximum depth of 21 m. The presence of crystalline rocks and a dolomite vein rich in gypsum in the catchment area makes the lake a typical “sulphuretum ” dominated by coupled carbon and sulphur...... cycles. The chemocline lies at about 12 m depth, stabilized by density differences of salt-rich water supplied by sub-aquatic springs to the monimolimnion and of electrolyte-poor surface water feeding the mixolimnion. Steep sulphide and light gradients in the chemocline support the growth of a large...... in the chemocline. Small-celled PSB together with the sulfate-reducing bacterium Desulfocapsa thiozymogenes sp. form stable aggregates in the lake, which represent small microenvironments with an internal sulphur cycle. Eukaryotic primary producers in the anoxic zones are dominated by Cryptomonas phaseolus...

  10. Playa Lakes

    Data.gov (United States)

    Kansas Data Access and Support Center — This digital dataset provides information about the spatial distribution of soil units associated with playa lakes. Specific soil types have been designated by the...

  11. Remote Sensing

    CERN Document Server

    Khorram, Siamak; Koch, Frank H; van der Wiele, Cynthia F

    2012-01-01

    Remote Sensing provides information on how remote sensing relates to the natural resources inventory, management, and monitoring, as well as environmental concerns. It explains the role of this new technology in current global challenges. "Remote Sensing" will discuss remotely sensed data application payloads and platforms, along with the methodologies involving image processing techniques as applied to remotely sensed data. This title provides information on image classification techniques and image registration, data integration, and data fusion techniques. How this technology applies to natural resources and environmental concerns will also be discussed.

  12. Characterizing meadow vegetation with multitemporal Landsat thematic mapper remote sensing.

    Science.gov (United States)

    Alan A. Ager; Karen E. Owens

    2004-01-01

    Wet meadows are important biological components in the Blue Mountains of eastern Oregon. Many meadows in the Blue Mountains and elsewhere in the Western United States are in a state of change owing to grazing, mining, logging, road development, and other factors. This project evaluated the utility of remotely sensed data to characterize and monitor meadow vegetation...

  13. Lake Nasser evaporation reduction study

    Directory of Open Access Journals (Sweden)

    Hala M.I. Ebaid

    2010-10-01

    Full Text Available This study aims to evaluate the reduction of evaporation of Lake Nasser’s water caused by disconnecting (fully or partially some of its secondary channels (khors. This evaluation integrates remote sensing, Geographic Information System (GIS techniques, aerodynamic principles, and Landsat7 ETM+ images. Three main procedures were carried out in this study; the first derived the surface temperature from Landsat thermal band; the second derived evaporation depth and approximate evaporation volume for the entire lake, and quantified evaporation loss to the secondary channels’ level over one month (March by applied aerodynamic principles on surface temperature of the raster data; the third procedure applied GIS suitability analysis to determine which of these secondary channels (khors should be disconnected. The results showed evaporation depth ranging from 2.73 mm/day at the middle of the lake to 9.58 mm/day at the edge. The evaporated water-loss value throughout the entire lake was about 0.86 billion m3/month (March. The analysis suggests that it is possible to save an approximate total evaporation volume loss of 19.7 million m3/month (March, and thus 2.4 billion m3/year, by disconnecting two khors with approximate construction heights of 8 m and 15 m. In conclusion, remote sensing and GIS are useful for applications in remote locations where field-based information is not readily available and thus recommended for decision makers remotely planning in water conservation and management.

  14. Regional distribution and relevance in paleonvironmental studies of lakes in the Tatra Mts. (Western Carpathians

    Directory of Open Access Journals (Sweden)

    Joanna POCIASK-KARTECZKA

    2014-11-01

    Full Text Available Scientific limnological research in the Tatra Mountains were initiated by Stanislaw Staszic in the early XIX century.  After the World War II, the evolution of Tatra lakes was investigated by Kondracki, Klimaszewski, Baumgart-Kotarba and. Extensive paleolimnological investigations in the Tatra Mountains were started by the group of scientists led by K. Starmach in the beginning of the second half of the 20th century. There has been not much research concerned to the regional distribution of lakes and their properties in the Tatra Mountains (Pociask-Karteczka 2013. Very early division of lakes presented A. Gadomski (1922, which distinguished four types of lakes: a tarns (cirque lake or corrie loch, b bedrock-dammed lakes, c moraine lakes. This division was concerned in subsequent publications (Choiński 2007. M. Lukniš (1973, 1985 recognized additional types: kettles and landslide-dammed lakes and M. Klimaszewski (1988 – inter-sheepback lakes. J. Pacl and K. Wit-Jóźwik in Klima Tatier (Pacl, Wit-Jóźwik 1974 were focused on the temperature of water in lakes in Polish and Slovak parts and M. Borowiak (2000a,b provided a comprehensive analysis of types, dimensions, temperature and chemical composition of water in lakes in the Tatra Mountains.According to present day state of knowledge, one may distinguish following genetic types of lakes: I glacial, II not-glacial. There are four types of the glacial origin lakes in the Tatra Mountains (Fig. 1: a tarns (cirque lakes or corrie loch, b bedrock-moraine dammed lakes, c inter-sheepback lakes, d moraine lakes, e kettles.Most of lakes in the Tatra Mountains are tarns and bedrock-moraine dammed lakes, and they are located at the elevation over 1400 m a.s.l. in the Western Tatra Mountains, and over 1600 m a.s.l. in the High Tatra Mountains. Some of them are paternoster lakes – a series of stair-stepped lakes formed in individual rock basins aligned down the course of a glaciated valley. Lakes in

  15. Pleistocene lake level changes in Western Mongolia

    Science.gov (United States)

    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

  16. Rocky Mountain Spotted Fever

    Science.gov (United States)

    ... with facebook share with twitter share with linkedin Rocky Mountain Spotted Fever Credit: CDC A male cayenne tick, Amblyomma cajennense, ... and New Mexico. Why Is the Study of Rocky Mountain Spotted Fever a Priority for NIAID? Tickborne diseases are becoming ...

  17. Rocky Mountain spotted fever

    Science.gov (United States)

    ... spotted fever on the foot Rocky Mountain spotted fever, petechial rash Antibodies Deer and dog tick References McElligott SC, Kihiczak GG, Schwartz RA. Rocky Mountain spotted fever and other rickettsial infections. In: Lebwohl MG, Heymann ...

  18. Principles of lake sedimentology

    International Nuclear Information System (INIS)

    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

  19. Application of remote sensing in aquatic ecosystems

    Science.gov (United States)

    Yousef, Foad

    I utilized state the art remote sensing and GIS (Geographical Information System) techniques to study large scale biological, physical and ecological processes of coastal, nearshore, and offshore waters of Lake Michigan and Lake Superior. These processes ranged from chlorophyll alpha and primary production time series analysies in Lake Michigan to coastal stamp sand threats on Buffalo Reef in Lake Superior. I used SeaWiFS (Sea-viewing Wide Field-of-view Sensor) satellite imagery to trace various biological, chemical and optical water properties of Lake Michigan during the past decade and to investigate the collapse of early spring primary production. Using spatial analysis techniques, I was able to connect these changes to some important biological processes of the lake (quagga mussels filtration). In a separate study on Lake Superior, using LiDAR (Light Detection and Ranging) and aerial photos, we examined natural coastal erosion in Grand Traverse Bay, Michigan, and discussed a variety of geological features that influence general sediment accumulation patterns and interactions with migrating tailings from legacy mining. These sediments are moving southwesterly towards Buffalo Reef, creating a threat to the lake trout and lake whitefish breeding ground.

  20. Savannah River Plant remote environmental monitoring system

    International Nuclear Information System (INIS)

    Schubert, J.F.

    1987-01-01

    The SRP remote environmental monitoring system consists of separations facilities stack monitors, production reactor stack monitors, twelve site perimeter monitors, river and stream monitors, a geostationary operational environmental satellite (GOES) data link, reactor cooling lake thermal monitors, meteorological tower system, Weather Information and Display (WIND) system computer, and the VANTAGE data base management system. The remote environmental monitoring system when fully implemented will provide automatic monitoring of key stack releases and automatic inclusion of these source terms in the emergency response codes

  1. Great Lakes

    Science.gov (United States)

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

    1998-01-01

    The Great Lakes region, as defined here, includes the Great Lakes and their drainage basins in Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. The region also includes the portions of Minnesota, Wisconsin, and the 21 northernmost counties of Illinois that lie in the Mississippi River drainage basin, outside the floodplain of the river. The region spans about 9º of latitude and 20º of longitude and lies roughly halfway between the equator and the North Pole in a lowland corridor that extends from the Gulf of Mexico to the Arctic Ocean.The Great Lakes are the most prominent natural feature of the region (Fig. 1). They have a combined surface area of about 245,000 square kilometers and are among the largest, deepest lakes in the world. They are the largest single aggregation of fresh water on the planet (excluding the polar ice caps) and are the only glacial feature on Earth visible from the surface of the moon (The Nature Conservancy 1994a).The Great Lakes moderate the region’s climate, which presently ranges from subarctic in the north to humid continental warm in the south (Fig. 2), reflecting the movement of major weather masses from the north and south (U.S. Department of the Interior 1970; Eichenlaub 1979). The lakes act as heat sinks in summer and heat sources in winter and are major reservoirs that help humidify much of the region. They also create local precipitation belts in areas where air masses are pushed across the lakes by prevailing winds, pick up moisture from the lake surface, and then drop that moisture over land on the other side of the lake. The mean annual frost-free period—a general measure of the growing-season length for plants and some cold-blooded animals—varies from 60 days at higher elevations in the north to 160 days in lakeshore areas in the south. The climate influences the general distribution of wild plants and animals in the region and also influences the activities and distribution of the human

  2. Observing a catastrophic thermokarst lake drainage in northern Alaska

    Science.gov (United States)

    Jones, Benjamin M.; Arp, Christopher D.

    2015-01-01

    The formation and drainage of thermokarst lakes have reshaped ice-rich permafrost lowlands in the Arctic throughout the Holocene. North of Teshekpuk Lake, on the Arctic Coastal Plain of northern Alaska, thermokarst lakes presently occupy 22.5% of the landscape, and drained thermokarst lake basins occupy 61.8%. Analysis of remotely sensed imagery indicates that nine lakes (>10 ha) have drained in the 1,750 km2 study area between 1955 and 2014. The most recent lake drainage was observed using in situ data loggers providing information on the duration and magnitude of the event, and a nearby weather station provided information on the environmental conditions preceding the lake drainage. Lake 195 (L195), an 80 ha thermokarst lake with an estimated water volume of ~872,000 m3, catastrophically drained on 05 July 2014. Abundant winter snowfall and heavy early summer precipitation resulted in elevated lake water levels that likely promoted bank overtopping, thermo-erosion along an ice-wedge network, and formation of a 9 m wide, 2 m deep, and 70 m long drainage gully. The lake emptied in 36 hours, with 75% of the water volume loss occurring in the first ten hours. The observed peak discharge of the resultant flood was 25 m3/s, which is similar to that in northern Alaska river basins whose areas are more than two orders of magnitude larger. Our findings support the catastrophic nature of sudden lake drainage events and the mechanistic hypotheses developed by J. Ross Mackay.

  3. Satellite remote sensing of limnological indicators of global change

    International Nuclear Information System (INIS)

    Wynne, R.H.; Lillesand, T.M.

    1991-01-01

    The paper examines the general hypothesis that large-scale and long-term trends in lake ice formation and breakup, along with changes in the optical properties of lakes, can serve as robust integrated measures of regional and global climate change. Recent variation in the periodicity of lake ice formation and breakup is investigated using the AVHRR aboard the NOAA/TIROS series of polar orbiting satellites. The study area consists of 44 lakes and reservoirs with a surface area of greater than 1000 hectares in Wisconsin. The utility of AVHRR for lake ice detection with high temporal resolution is demonstrated, the relationship between ice phenology and periodicity with lake morphometry for the lakes in the study is elucidated, and remotely sensed measures of ice periodicity are correlated with local and regional temperature trends. 31 refs

  4. Phylogenetic Diversity of Archaea and Bacteria in the Anoxic Zone of a Meromictic Lake (Lake Pavin, France)▿ †

    Science.gov (United States)

    Lehours, Anne-Catherine; Evans, Paul; Bardot, Corinne; Joblin, Keith; Gérard, Fonty

    2007-01-01

    The compositions of archaeal and bacterial populations at different depths (60 m [mixolimnion-chemocline interface], 70 m [chemocline-subchemocline interface], 90 m, and 92 m [the water-sediment interface]) in the anoxic zone of the water column in Lake Pavin, a freshwater permanently stratified mountain lake in France, were determined. Phylogenetic trees were constructed from sequences to assess archaeal and bacterial diversity at the four sites. PMID:17261512

  5. Geologic reconnaissance of the Hot Springs Mountains, Churchill County, Nevada

    Science.gov (United States)

    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)

  6. Aerobic biodegradation potential of endocrine-disrupting chemicals in surface-water sediment at Rocky Mountain National Park, USA.

    Science.gov (United States)

    Bradley, Paul M; Battaglin, William A; Iwanowicz, Luke R; Clark, Jimmy M; Journey, Celeste A

    2016-05-01

    Endocrine-disrupting chemicals (EDCs) in surface water and bed sediment threaten the structure and function of aquatic ecosystems. In natural, remote, and protected surface-water environments where contaminant releases are sporadic, contaminant biodegradation is a fundamental driver of exposure concentration, timing, duration, and, thus, EDC ecological risk. Anthropogenic contaminants, including known and suspected EDCs, were detected in surface water and sediment collected from 2 streams and 2 lakes in Rocky Mountain National Park (Colorado, USA). The potential for aerobic EDC biodegradation was assessed in collected sediments using 6 (14) C-radiolabeled model compounds. Aerobic microbial mineralization of natural (estrone and 17β-estradiol) and synthetic (17α-ethinylestradiol) estrogen was significant at all sites. Bed sediment microbial communities in Rocky Mountain National Park also effectively degraded the xenoestrogens bisphenol-A and 4-nonylphenol. The same sediment samples exhibited little potential for aerobic biodegradation of triclocarban, however, illustrating the need to assess a wider range of contaminant compounds. The present study's results support recent concerns over the widespread environmental occurrence of carbanalide antibacterials, like triclocarban and triclosan, and suggest that backcountry use of products containing these compounds should be discouraged. Published 2015 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.

  7. Geological remote sensing-evaluation of image data

    Energy Technology Data Exchange (ETDEWEB)

    Nagatani, H

    1977-01-01

    During the nationwide geothermal investigation program (Japan) begun in 1973, five districts were chosen for evaluation of the effectiveness and limitations of aerial thermography. Using thermal images of Ibusuki City and Yamakawa-cho, geothermal resource areas were detected and related fracture zones were established by combining the thermal imagery and geological maps. At Ibusuki City, it was determined that the heat source was the Ata caldera, and that a fracture system connecting it to Lake Ikeda provides a conduit for geothermal fluids. Image plotting of thermal anomalies in the Hachimantai geothermal field was found to be an effective method for monitoring variation in thermal activity. LANDSAT imagery was anlayzed and lineament systems were detected in the mountains of the Kanto district. Followup of LANDSAT data by mapping teams confirmed a fault which intersects the major Kamitsuna fault in that district. This successful use of remote sensing data is encouraging but it is possible to draw only limited conclusions from it at present. Further refinement of analytical techniques is required.

  8. Examining land-use/land-cover change in the Lake Dianchi watershed of the Yunnan-Guizhou Plateau of Southwest China with remote sensing and GIS techniques: 1974–2008.

    Science.gov (United States)

    Zhao, Yaolong; Zhang, Ke; Fu, Yingchun; Zhang, Hong

    2012-10-24

    Monitoring land-use/land-cover change (LULCC) and exploring its mechanisms are important processes in the environmental management of a lake watershed. The purpose of this study was to examine the spatiotemporal pattern of LULCC by using multi landscape metrics in the Lake Dianchi watershed, which is located in the Yunnan-Guizhou Plateau of Southwest China. Landsat images from the years 1974, 1988, 1998, and 2008 were analyzed using geographical information system (GIS) techniques. The results reveal that land-use/land-cover has changed greatly in the watershed since 1974. This change in land use structure was embodied in the rapid increase of developed areas with a relative change rate of up to 324.4%. The increase in developed areas mainly occurred in agricultural land, especially near the shores of Lake Dianchi. The spatial pattern and structure of the change was influenced by the urban sprawl of the city of Kunming. The urban sprawl took on the typical expansion mode of cyclic structures and a jigsaw pattern and expanded to the shore of Lake Dianchi. Agricultural land changed little with respect to the structure but changed greatly in the spatial pattern. The landscape in the watershed showed a trend of fragmentation with a complex boundary. The dynamics of land-use/land-cover in the watershed correlate with land-use policies and economic development in China.

  9. The remote sensing of aquatic macrophytes Part 1: Color-infrared aerial photography as a tool for identification and mapping of littoral vegetation. Part 2: Aerial photography as a quantitative tool for the investigation of aquatic ecosystems. [Lake Wingra, Wisconsin

    Science.gov (United States)

    Gustafson, T. D.; Adams, M. S.

    1973-01-01

    Research was initiated to use aerial photography as an investigative tool in studies that are part of an intensive aquatic ecosystem research effort at Lake Wingra, Madison, Wisconsin. It is anticipated that photographic techniques would supply information about the growth and distribution of littoral macrophytes with efficiency and accuracy greater than conventional methods.

  10. Use of Remote Sensing Data and GIS Tools for Seismic Hazard Assessment for Shallow Oilfields and its Impact on the Settlements at Masjed-i-Soleiman Area, Zagros Mountains, Iran

    Directory of Open Access Journals (Sweden)

    Hojjat Ollah Safari

    2010-05-01

    Full Text Available Masjed-i-Soleiman (MIS is situated in the northern part of the Dezful embayment, which is in the Zagros fold–thrust belt with high seismic activities. MIS faces a shallow buried anticline, formed by the shallowest oilfield with a thick gas cap. The cap rocks of this oilfield are highly fractured, which has resulted in leakages from the gas cap. In this paper, we have used remote sensing techniques and image interpretation for the identification of the Niayesh, Lahbari, Andika and MIS fault zones in the studied area. Further, the study exploited seismic potential mapping using the remote sensing techniques. The relationships between the structural controls and localized gas leakage are assessed within the GIS environment. Additionally, field observation data corroborated that the leakages (and seepages are smashed within the intersection of Niayesh and MIS fault zone, which belongs to the high fractured hinge zone of the MIS anticline. As a result, the reactivation of these active faults may cause large earthquakes with a maximum magnitude of between 6.23 < Ms < 7.05 (Richter scale and maximum horizontal acceleration 0.26 < a < 0.55 g. Finally, the authors concluded that this anticipated earthquake may cause large scale fracturing of cap rocks, releasing a large volume of H2S gas from the uppermost layer of the reservoir.

  11. Mountain Plover [ds109

    Data.gov (United States)

    California Natural Resource Agency — Point locations representing observations of mountain plover (Charadrius montanus) feeding and roosting flocks (and occasional individuals) documented during an...

  12. An improved active contour model for glacial lake extraction

    Science.gov (United States)

    Zhao, H.; Chen, F.; Zhang, M.

    2017-12-01

    Active contour model is a widely used method in visual tracking and image segmentation. Under the driven of objective function, the initial curve defined in active contour model will evolve to a stable condition - a desired result in given image. As a typical region-based active contour model, C-V model has a good effect on weak boundaries detection and anti noise ability which shows great potential in glacial lake extraction. Glacial lake is a sensitive indicator for reflecting global climate change, therefore accurate delineate glacial lake boundaries is essential to evaluate hydrologic environment and living environment. However, the current method in glacial lake extraction mainly contains water index method and recognition classification method are diffcult to directly applied in large scale glacial lake extraction due to the diversity of glacial lakes and masses impacted factors in the image, such as image noise, shadows, snow and ice, etc. Regarding the abovementioned advantanges of C-V model and diffcults in glacial lake extraction, we introduce the signed pressure force function to improve the C-V model for adapting to processing of glacial lake extraction. To inspect the effect of glacial lake extraction results, three typical glacial lake development sites were selected, include Altai mountains, Centre Himalayas, South-eastern Tibet, and Landsat8 OLI imagery was conducted as experiment data source, Google earth imagery as reference data for varifying the results. The experiment consequence suggests that improved active contour model we proposed can effectively discriminate the glacial lakes from complex backgound with a higher Kappa Coefficient - 0.895, especially in some small glacial lakes which belongs to weak information in the image. Our finding provide a new approach to improved accuracy under the condition of large proportion of small glacial lakes and the possibility for automated glacial lake mapping in large-scale area.

  13. International Planning for Subglacial Lake Exploration

    Science.gov (United States)

    Kennicutt, M.; Priscu, J.

    2003-04-01

    As one of the last unexplored frontiers on our planet, subglacial lakes offer a unique and exciting venue for exploration and research. Over the past several years, subglacial lakes have captured the imagination of the scientific community and public, evoking images of potential exotic life forms surviving under some of the most extreme conditions on earth. Various planning activities have recognized that due to the remote and harsh conditions, that a successful subglacial lake exploration program will entail a concerted effort for a number of years. It will also require an international commitment of major financial and human resources. To begin a detailed planning process, the Scientific Committee on Antarctic Research (SCAR) convened the Subglacial Antarctic Lake Exploration Group of Specialists (SALEGOS) in Tokyo in 2000. The group was asked to build on previous workshops and meetings to develop a plan to explore subglacial lake environments. Its mandate adopted the guiding principles as agreed in Cambridge in 1999 that the program would be interdisciplinary in scope, be designed for minimum contamination and disturbance of the subglacial lake environment, have as a goal lake entry and sample retrieval, and that the ultimate target of the program should be Lake Vostok exploration. Since its formation SALEGOS has met three times and addressed some of the more intractable issues related to subglacial lake exploration. Topics under discussion include current state-of-the-knowledge of subglacial environments, technological needs, international management and organizational strategies, a portfolio of scientific projects, "clean" requirements, and logistical considerations. In this presentation the actvities of SALEGOS will be summarized and recommendations for an international subglacial lake exploration program discussed.

  14. Bathymetry of Lake Michigan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Michigan has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  15. Bathymetry of Lake Ontario

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Ontario has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  16. Bathymetry of Lake Superior

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Superior has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  17. Great Lakes Bathymetry

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lakes Michigan, Erie, Saint Clair, Ontario and Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and...

  18. Bathymetry of Lake Huron

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  19. Macroinvertebrates as indicators of fish absence in naturally fishless lakes

    Science.gov (United States)

    Schilling, Emily Gaenzle; Loftin, C.S.; Huryn, Alexander D.

    2009-01-01

    1. Little is known about native communities in naturally fishless lakes in eastern North America, a region where fish stocking has led to a decline in these habitats. 2. Our study objectives were to: (i) characterise and compare macroinvertebrate communities in fishless lakes found in two biophysical regions of Maine (U.S.A.): kettle lakes in the eastern lowlands and foothills and headwater lakes in the central and western mountains; (ii) identify unique attributes of fishless lake macroinvertebrate communities compared to lakes with fish and (iii) develop a method to efficiently identify fishless lakes when thorough fish surveys are not possible. 3. We quantified macroinvertebrate community structure in the two physiographic fishless lake types (n = 8 kettle lakes; n = 8 headwater lakes) with submerged light traps and sweep nets. We also compared fishless lake macroinvertebrate communities to those in fish-containing lakes (n = 18) of similar size, location and maximum depth. We used non-metric multidimensional scaling to assess differences in community structure and t-tests for taxon-specific comparisons between lakes. 4. Few differences in macroinvertebrate communities between the two physiographic fishless lake types were apparent. Fishless and fish-containing lakes had numerous differences in macroinvertebrate community structure, abundance, taxonomic composition and species richness. Fish presence or absence was a stronger determinant of community structure in our study than differences in physical conditions relating to lake origin and physiography. 5. Communities in fishless lakes were more speciose and abundant than in fish-containing lakes, especially taxa that are large, active and free-swimming. Families differing in abundance and taxonomic composition included Notonectidae, Corixidae, Gyrinidae, Dytiscidae, Aeshnidae, Libellulidae and Chaoboridae. 6. We identified six taxa unique to fishless lakes that are robust indicators of fish absence: Graphoderus

  20. A lineament analysis of Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Perry, J.J.

    1988-01-01

    The Nuclear Waste Policy Act of 1982 was signed into law on January 7, 1983. It specifies procedures for the Department of Energy in the selection of a high level nuclear waste repository. Federal Environmental Protection Agency standards require adequate isolation of waste from the biosphere for 10,000 years. The law considers such geologic factors as tectonic stability, igneous activity, hydrologic conditions and natural resources to be of primary concern. Yucca Mountain in southern Nevada is one of three sites selected for further consideration in the site characterization process. The Nuclear Waste Project Office (NWPO) within the Agency for Nuclear Projects of the State of Nevada is conducting an independent scientific assessment of the proposed site. The remote sensing technical assessment is one of seven task groups conducting review and research into the suitability of Yucca Mountain. The study undertaken by the Remote Sensing Group was that of a lineament analysis with regard to the site's structural relationship within a regional tectonic framework. Lineaments mapped from synoptic imagery may prove to represent structural zones of weakness. These zones may provide pathways for the infiltration of groundwater, conduits for the extrusion of magma or be reactivated as stress conditions change. This paper describes the methodology for a lineament analysis of the Yucca Mountain area

  1. Great Lakes Science Center

    Data.gov (United States)

    Federal Laboratory Consortium — Since 1927, Great Lakes Science Center (GLSC) research has provided critical information for the sound management of Great Lakes fish populations and other important...

  2. Potential transport pathways of dust emanating from the playa of Ebinur Lake, Xinjiang, in arid northwest China

    Science.gov (United States)

    Ge, Yongxiao; Abuduwaili, Jilili; Ma, Long; Wu, Na; Liu, Dongwei

    2016-09-01

    In this paper, the HYSPLIT model, driven with reanalysis meteorological data from 1978 to 2013, was used to understand the potential transport characteristics of dust and salt dust emanating from the playa of Ebinur Lake in arid northwest China. Daily air parcel trajectories were computed forward for 8 days from an origin centered over Ebinur Lake at 100 m above ground level. Air parcel trajectory density plots were mapped for seven levels: 0-100 m agl., 100-500 m agl., 500-1000 m agl., 1000-1500 m agl., 1500-2000 m agl., 2000-3000 m agl., and 3000-5000 m agl. These show that potential dust transport pathways have clear seasonal differentiation. The potential transport distance of dust and salt dust is greatest in spring and summer. In autumn and winter, the potential transport of the high-density air trajectory is below 1000 m traveling a shorter distance. Potential dust transport pathways showed notifying directivity in different seasons and heights. Southeast in spring and summer, and north to northeast in autumn and winter are the two main potential transport channels of dust and salt dust. Accordingly, dust and salt dust from the playa of Ebinur Lake may influence the atmospheric processes and biogeochemical cycles of a vast region. The main area of influence of dust and salt dust is close to the source area, and will significantly accelerate the melting of snow and ice in the Tianshan Mountains. This highlights the urgent need to combine remote sensing, isotope and other methods to further research the transport characteristics of dust and salt dust from the playa of the Ebinur Lake.

  3. Fish populations in a large group of acid-stressed lakes

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, H H

    1975-01-01

    The purpose of this study was to determine the effects of environmental stress on the number and diversity of fish species in a group of acid-stressed lakes. The study area was the La Cloche Mountains, a series of quartzite ridges covering 1,300 km/sup 2/ along the north shore of Georgian Bay and north channel of Lake Huron. Within these ridges are 173 lakes; 68 of the largest of these made up the study sample. The lakes of the La Cloche Mountains are undergoing rapid acidification. Coincident with this there has been the loss of sport fishes from several lakes. Lakes such as Nellie, Lumsden, O.S.A., Acid and Killarney supported good sport fisheries for the lake trout, (Salvelinus namaycush) for many years, but have ceased to do so in the last 5 to 15 years. Other sport fishes, notably the walleye (Stizostedion vitreum) and smallmouth bass (micropterus dolomieu) have disappeared from some of the La Cloche Lakes. Thus recreational fishing alone could not have been the cause of the change. Beamish (1974) recorded the extreme sparcity of the three remaining fish species in O.S.A. Lake. Many of the lakes of the La Cloche mountains are accessible only with difficulty and little or no information exists for these lakes prior to this study. This precluded simple comparison of these lakes before and during acidification. This lack of historic data determined in part the approach taken in this study; a comparison of the fish communities of a group of lakes differing in degree of acid stress.

  4. Historical telecommunication in the Hindukush-Karakoram-Himalayas: An ancient early warning system for glacier lake outbursts

    Science.gov (United States)

    Iturrizaga, Lasafam

    2016-04-01

    Mountain societies are in a crucial transition phase in terms of the management of natural hazards. Advances in geographic technologies, such as a variety of remote-sensing tools and mobile communication systems, have drastically changed the way of early warning methods in difficult accessible high mountain environments compared to those of ancient times. In order to implement new natural hazard policies, it is essential to unravel the traditional ways of disaster management which is presented here by a case study from the Hindukush-Karakoram-Himalayas. In the rugged relief of the Himalaya Region, the exchange of information was a labor-intensive and time-consuming task for remote high mountain villages before the infrastructural development and the introduction of modern communication systems. Therefore, early warning of natural hazards with long run-out distances seems to have been rather impossible. However, in the present study a historical optical long-distance and fast operating communication system over horizontal distances of several hundred kilometers was discovered during field investigations in the Hindukush-Karakoram and the transmission paths reconstructed in the following years. The so called Puberanch-system relied on a chain of fire signals as used by ancient societies in other mountain and coastal environments in the world. It was originally in use for the alert against war attacks from hostile neighboring communities. Later on, it served as an early warning system for glacier lake outbursts, which have been in the end of the 19th century and beginning of the 20th century one of the most devastating natural hazards in the region. Remarkable is the fact that fire posts were located in extremely harsh environments at altitudes above 4000 m requiring a highly sophisticated supply system of fire wood and food. Interviews with local inhabitants, the evaluation of historical travel records and international newspapers proved, that the system has been

  5. Advances in global mountain geomorphology

    Science.gov (United States)

    Slaymaker, Olav; Embleton-Hamann, Christine

    2018-05-01

    Three themes in global mountain geomorphology have been defined and reinforced over the past decade: (a) new ways of measuring, sensing, and analyzing mountain morphology; (b) a new emphasis on disconnectivity in mountain geomorphology; and (c) the emergence of concerns about the increasing influence of anthropogenic disturbance of the mountain geomorphic environment, especially in intertropical mountains where population densities are higher than in any other mountain region. Anthropogenically induced hydroclimate change increases geomorphic hazards and risks but also provides new opportunities for mountain landscape enhancement. Each theme is considered with respect to the distinctiveness of mountain geomorphology and in relation to important advances in research over the past decade. The traditional reliance on the high energy condition to define mountain geomorphology seems less important than the presence of unique mountain landforms and landscapes and the distinctive ways in which human activity and anthropogenically induced hydroclimate change are transforming mountain landscapes.

  6. Lake Cadagno

    DEFF Research Database (Denmark)

    Tonolla, Mauro; Storelli, Nicola; Danza, Francesco

    2017-01-01

    cycles. The chemocline lies at about 12 m depth, stabilized by density differences of salt-rich water supplied by sub-aquatic springs to the monimolimnion and of electrolyte-poor surface water feeding the mixolimnion. Steep sulphide and light gradients in the chemocline support the growth of a large...... in the chemocline. Small-celled PSB together with the sulfate-reducing bacterium Desulfocapsa thiozymogenes sp. form stable aggregates in the lake, which represent small microenvironments with an internal sulphur cycle. Eukaryotic primary producers in the anoxic zones are dominated by Cryptomonas phaseolus...

  7. Remote viewing.

    Science.gov (United States)

    Scott, C

    1988-04-15

    Remote viewing is the supposed faculty which enables a percipient, sited in a closed room, to describe the perceptions of a remote agent visiting an unknown target site. To provide convincing demonstration of such a faculty poses a range of experimental and practical problems, especially if feedback to the percipient is allowed after each trial. The precautions needed are elaborate and troublesome; many potential loopholes have to be plugged and there will be strong temptations to relax standards, requiring exceptional discipline and dedication by the experimenters. Most reports of remote viewing experiments are rather superficial and do not permit assessment of the experimental procedures with confidence; in many cases there is clear evidence of particular loopholes left unclosed. Any serious appraisal of the evidence would have to go beyond the reports. Meanwhile the published evidence is far from compelling, and certainly insufficient to justify overthrow of well-established scientific principles.

  8. Geohydrology and evapotranspiration at Franklin Lake Playa, Inyo County, California

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-12-01

    Franklin Lake playa is one of the principal discharge areas of the Furnace Creek Ranch-Alkali Flat ground-water-flow system in southern Nevada and adjacent California. Yucca Mountain, Nevada, located within this flow system, is being evaluated by the US Department of Energy to determine its suitability as a potential site for a high-level nuclear-waste repository. To assist the US Department of Energy with its evaluation of the Yucca Mountain site, the US Geological Survey developed a parameter-estimation model of the Furnace Creek Ranch-Alkali Flat ground-water-flow system. Results from sensitivity analyses made using the parameter-estimation model indicated that simulated rates of evapotranspiration at Franklin Lake playa had the largest effect on the calculation of transmissivity values at Yucca Mountain of all the model-boundary conditions and, therefore, that evapotranspiration required careful definition. 72 refs., 59 figs., 26 tab.

  9. Geohydrology and evapotranspiration at Franklin Lake Playa, Inyo County, California

    International Nuclear Information System (INIS)

    1990-01-01

    Franklin Lake playa is one of the principal discharge areas of the Furnace Creek Ranch-Alkali Flat ground-water-flow system in southern Nevada and adjacent California. Yucca Mountain, Nevada, located within this flow system, is being evaluated by the US Department of Energy to determine its suitability as a potential site for a high-level nuclear-waste repository. To assist the US Department of Energy with its evaluation of the Yucca Mountain site, the US Geological Survey developed a parameter-estimation model of the Furnace Creek Ranch-Alkali Flat ground-water-flow system. Results from sensitivity analyses made using the parameter-estimation model indicated that simulated rates of evapotranspiration at Franklin Lake playa had the largest effect on the calculation of transmissivity values at Yucca Mountain of all the model-boundary conditions and, therefore, that evapotranspiration required careful definition. 72 refs., 59 figs., 26 tab

  10. Ground-based Fabry-Perot interferometry of the terrestrial nightglow with a bare charge-coupled device; Remote field site deployment

    International Nuclear Information System (INIS)

    Niciejewski, R.; Killeen, T.L.; Turnbull, M.

    1994-01-01

    The application of Fabry-Perot interferometers (FPIs) to the study of upper atmosphere thermodynamics has largely been restricted by the very low light levels in the terrestrial airglow as well as the limited range in wavelength of photomultiplier tube (PMT) technology. During the past decade, the development of the scientific grade charge-coupled device (CCD) has progressed to the stage in which the detector has become the logical replacement for the PMT. Small fast microcomputers have made it possible to ''upgrade'' the remote field sites which bare CCDs and not only retain the previous capabilities of the existing FPIs but expand the data coverage in both temporal and wavelength domains. The problems encountered and the solutions applied to the deployment of a bare CCD, with data acquisition and image reduction techniques, are discussed. Sample geophysical data determined from the FPI fringe profiles are shown for stations at Peach Mountain, Michigan, and Watson Lake, Yukon Territory

  11. Estimating Spring Condensation on the Great Lakes

    Science.gov (United States)

    Meyer, A.; Welp, L.

    2017-12-01

    The Laurentian Great Lakes region provides opportunities for shipping, recreation, and consumptive water use to a large part of the United States and Canada. Water levels in the lakes fluctuate yearly, but attempts to model the system are inadequate because the water and energy budgets are still not fully understood. For example, water levels in the Great Lakes experienced a 15-year low period ending in 2013, the recovery of which has been attributed partially to decreased evaporation and increased precipitation and runoff. Unlike precipitation, the exchange of water vapor between the lake and the atmosphere through evaporation or condensation is difficult to measure directly. However, estimates have been constructed using off-shore eddy covariance direct measurements of latent heat fluxes, remote sensing observations, and a small network of monitoring buoys. When the lake surface temperature is colder than air temperature as it is in spring, condensation is larger than evaporation. This is a relatively small component of the net annual water budget of the lakes, but the total amount of condensation may be important for seasonal energy fluxes and atmospheric deposition of pollutants and nutrients to the lakes. Seasonal energy fluxes determine, and are influenced by, ice cover, water and air temperatures, and evaporation in the Great Lakes. We aim to quantify the amount of spring condensation on the Great Lakes using the National Center for Atmospheric Prediction North American Regional Reanalysis (NCEP NARR) Data for Winter 2013 to Spring 2017 and compare the condensation values of spring seasons following high volume, high duration and low volume, low duration ice cover.

  12. Response of lake chemistry to atmospheric deposition and climate in selected Class I wilderness areas in the western United States, 1993-2009

    Science.gov (United States)

    Mast, M. Alisa

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Forest Service, Air Resource Management, conducted a study to evaluate long-term trends in lake-water chemistry for 64 high-elevation lakes in selected Class I wilderness areas in Colorado, Idaho, Utah, and Wyoming during 1993 to 2009. Understanding how and why lake chemistry is changing in mountain areas is essential for effectively managing and protecting high-elevation aquatic ecosystems. Trends in emissions, atmospheric deposition, and climate variables (air temperature and precipitation amount) were evaluated over a similar period of record. A main objective of the study was to determine if changes in atmospheric deposition of contaminants in the Rocky Mountain region have resulted in measurable changes in the chemistry of high-elevation lakes. A second objective was to investigate linkages between lake chemistry and air temperature and precipitation to improve understanding of the sensitivity of mountain lakes to climate variability.

  13. Yucca Mountain digital database

    International Nuclear Information System (INIS)

    Daudt, C.R.; Hinze, W.J.

    1992-01-01

    This paper discusses the Yucca Mountain Digital Database (DDB) which is a digital, PC-based geographical database of geoscience-related characteristics of the proposed high-level waste (HLW) repository site of Yucca Mountain, Nevada. It was created to provide the US Nuclear Regulatory Commission's (NRC) Advisory Committee on Nuclear Waste (ACNW) and its staff with a visual perspective of geological, geophysical, and hydrological features at the Yucca Mountain site as discussed in the Department of Energy's (DOE) pre-licensing reports

  14. An overview of the recent palaeolimnology of selected lakes in the Romanian Carpathians

    Directory of Open Access Journals (Sweden)

    Simon M. HUTCHINSON

    2011-06-01

    Full Text Available Lakesediments can act as sensitive monitors of environmental change and human impacts. The Romanian Carpathians hold a significant number of glacial lakes and transverse a region of considerable environmental concerns, but relatively sparse environmental data and little recent lake sediment based research. Findings from selected lakes in two of the highest sections of these mountains inRomaniaare presented. In addition the palaeolimnological record held in the surficial sediments of other lower elevations sites in theEastern Carpathiansis also discussed. These sites are situated in contrasting sites comprising a volcanic crater lake (Lacul Sfânta Ana,HarghitaMountains and a lake dammed by land sliding (Lacul Iezer-Feredeu, Obcina Feredeului. 

  15. Anaglyph, Salt Lake City, Utah

    Science.gov (United States)

    2002-01-01

    The 2002 Winter Olympics are hosted by Salt Lake City at several venues within the city, in nearby cities, and within the adjacent Wasatch Mountains. This anaglyph image provides a stereoscopic map view of north central Utah that includes all of these Olympic sites. In the south, next to Utah Lake, Provo hosts the ice hockey competition. In the north, northeast of the Great Salt Lake, Ogden hosts curling and the nearby Snowbasin ski area hosts the downhill events. In between, southeast of the Great Salt Lake, Salt Lake City hosts the Olympic Village and the various skating events. Further east, across the Wasatch Mountains, the Park City ski resort hosts the bobsled, ski jumping, and snowboarding events. The Winter Olympics are always hosted in mountainous terrain. This view shows the dramatic landscape that makes the Salt Lake City region a world-class center for winter sports.The stereoscopic effect of this anaglyph was created by first draping a Landsat satellite image over a Shuttle Radar Topography Mission digital elevation model and then generating two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter.Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive, managed by the U.S. Geological Survey (USGS).Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed

  16. Planning for Community Based Tourism in a Remote Location

    Directory of Open Access Journals (Sweden)

    Sharon Harwood

    2010-07-01

    Full Text Available Remote areas are difficult to access, tend to lack critical infrastructure, are highly susceptible to shocks in the marketplace, and are perceived by industry to possess limited development opportunities. Accordingly a community orientated and territorial approach to development planning in a remote area will be more successful than a top down industry based approach [1]. Given the limitations of being remote, the case study community examined in this research manages and sustains a bird watching tourism product within a global market place. This paper examines how a remotely located community in the Arfak Mountains of West Papua overcomes these difficulties and plans for community based tourism (CBT in their locale.

  17. A hierarchic approach for examining panarctic vegeta0on with a focus on the linkages between remote-sensing and plot-based studies: A prototype example from Toolik Lake, Alaska

    DEFF Research Database (Denmark)

    Walker, D.A.; Bhatt, U.S.; Breen, A.L.

    A circumpolar view of Arctic vegetation developed with the advent of satellite-derived remote-sensing products. Interpretations of what the revealed patterns mean are dependent on a foundation of in-situ plot-based observations. Despite the importance of ground-based observations, only a few areas...... of species composition, canopy structure, biomass, leaf-area index, and NDVI, along with high-resolution satellite-based remote-sensing products at the same time....... classification, plot markings, and standardized approaches to describe the local environment, including photo points showing the vegetation and soils up close and in landscape view. (3) Standardized approaches for collecting in-situ time-series of spectral data. Standardized methods for collecting and analyzing...

  18. Snowmelt Timing as a Determinant of Lake Inflow Mixing

    Science.gov (United States)

    Roberts, D. C.; Forrest, A. L.; Sahoo, G. B.; Hook, S. J.; Schladow, S. G.

    2018-02-01

    Snowmelt is a significant source of carbon, nutrient, and sediment loads to many mountain lakes. The mixing conditions of snowmelt inflows, which are heavily dependent on the interplay between snowmelt and lake thermal regime, dictate the fate of these loads within lakes and their ultimate impact on lake ecosystems. We use five decades of data from Lake Tahoe, a 600 year residence-time lake where snowmelt has little influence on lake temperature, to characterize the snowmelt mixing response to a range of climate conditions. Using stream discharge and lake profile data (1968-2017), we find that the proportion of annual snowmelt entering the lake prior to the onset of stratification increases as annual snowpack decreases, ranging from about 50% in heavy-snow years to close to 90% in warm, dry years. Accordingly, in 8 recent years (2010-2017) where hourly inflow buoyancy and discharge could be quantified, we find that decreased snowpack similarly increases the proportion of annual snowmelt entering the lake at weak to positive buoyancy. These responses are due to the stronger effect of winter precipitation conditions on streamflow timing and temperature than on lake stratification, and point toward increased nearshore and near-surface mixing of inflows in low-snowpack years. The response of inflow mixing conditions to snowpack is apparent when isolating temperature effects on snowpack. Snowpack levels are decreasing due to warming temperatures during winter precipitation. Thus, our findings suggest that climate change may lead to increased deposition of inflow loads in the ecologically dynamic littoral zone of high-residence time, snowmelt-fed lakes.

  19. Education and Yucca Mountain

    International Nuclear Information System (INIS)

    Lamont, M.A.

    1995-01-01

    This paper outlines a middle school social studies curriculum taught in Nevada. The curriculum was designed to educate students about issues related to the Yucca Mountain project. The paper focuses on the activities used in the curriculum

  20. Recreational mountain biking injuries.

    Science.gov (United States)

    Aitken, S A; Biant, L C; Court-Brown, Charles M

    2011-04-01

    Mountain biking is increasing in popularity worldwide. The injury patterns associated with elite level and competitive mountain biking are known. This study analysed the incidence, spectrum and risk factors for injuries sustained during recreational mountain biking. The injury rate was 1.54 injuries per 1000 biker exposures. Men were more commonly injured than women, with those aged 30-39 years at highest risk. The commonest types of injury were wounding, skeletal fracture and musculoskeletal soft tissue injury. Joint dislocations occurred more commonly in older mountain bikers. The limbs were more commonly injured than the axial skeleton. The highest hospital admission rates were observed with head, neck and torso injuries. Protective body armour, clip-in pedals and the use of a full-suspension bicycle may confer a protective effect.

  1. Landforms of High Mountains

    Directory of Open Access Journals (Sweden)

    Derek A. McDougall

    2016-05-01

    Full Text Available Reviewed: Landforms of High Mountains. By Alexander Stahr and Ewald Langenscheidt. Heidelberg, Germany: Springer, 2015. viii + 158 pp. US$ 129.99. Also available as an e-book. ISBN 978-3-642-53714-1.

  2. Acute mountain sickness

    Science.gov (United States)

    ... GO About MedlinePlus Site Map FAQs Customer Support Health Topics Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Acute mountain sickness URL of this page: //medlineplus.gov/ency/article/ ...

  3. Climatic changes inferred fron analyses of lake-sediment cores, Walker Lake, Nevada

    International Nuclear Information System (INIS)

    Yang, In Che.

    1989-01-01

    Organic and inorganic fractions of sediment collected from the bottom of Walker Lake, Nevada, have been dated by carbon-14 techniques. Sedimentation rates and the organic-carbon content of the sediment were correlated with climatic change. The cold climate between 25,000 and 21,000 years ago caused little runoff, snow accumulation on the mountains, and rapid substantial glacial advances; this period of cold climate resulted in a slow sedimentation rate (0.20 millimeter per year) and in a small organic-carbon content in the sediment. Also, organic-carbon accumulation rates in the lake during this period were slow. The most recent period of slow sedimentation rate and small organic-carbon content occurred between 10,000 and 5500 years ago, indicative of low lake stage and dry climatic conditions. This period of dry climate also was evidenced by dry conditions for Lake Lahontan in Nevada and Searles Lake in California, as cited in the literature. Walker Lake filled rapidly with water between 5500 and 4500 years ago. The data published in this report was not produced under an approved Site Investigation Plan (SIP) or Study Plan (SP) and will not be used in the licensing process. 10 refs., 3 figs., 2 tabs

  4. Dissolved organic carbon and its potential predictors in eutrophic lakes.

    Science.gov (United States)

    Toming, Kaire; Kutser, Tiit; Tuvikene, Lea; Viik, Malle; Nõges, Tiina

    2016-10-01

    Understanding of the true role of lakes in the global carbon cycle requires reliable estimates of dissolved organic carbon (DOC) and there is a strong need to develop remote sensing methods for mapping lake carbon content at larger regional and global scales. Part of DOC is optically inactive. Therefore, lake DOC content cannot be mapped directly. The objectives of the current study were to estimate the relationships of DOC and other water and environmental variables in order to find the best proxy for remote sensing mapping of lake DOC. The Boosted Regression Trees approach was used to clarify in which relative proportions different water and environmental variables determine DOC. In a studied large and shallow eutrophic lake the concentrations of DOC and coloured dissolved organic matter (CDOM) were rather high while the seasonal and interannual variability of DOC concentrations was small. The relationships between DOC and other water and environmental variables varied seasonally and interannually and it was challenging to find proxies for describing seasonal cycle of DOC. Chlorophyll a (Chl a), total suspended matter and Secchi depth were correlated with DOC and therefore are possible proxies for remote sensing of seasonal changes of DOC in ice free period, while for long term interannual changes transparency-related variables are relevant as DOC proxies. CDOM did not appear to be a good predictor of the seasonality of DOC concentration in Lake Võrtsjärv since the CDOM-DOC coupling varied seasonally. However, combining the data from Võrtsjärv with the published data from six other eutrophic lakes in the world showed that CDOM was the most powerful predictor of DOC and can be used in remote sensing of DOC concentrations in eutrophic lakes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Limnology of Eifel maar lakes

    National Research Council Canada - National Science Library

    Scharf, Burkhard W; Björk, Sven

    1992-01-01

    ... & morphometry - Physical & chemical characteristics - Calcite precipitation & solution in Lake Laacher See - Investigations using sediment traps in Lake Gemundener Maar - Phytoplankton of Lake Weinfelder Maar...

  6. YUCCA MOUNTAIN SITE DESCRIPTION

    International Nuclear Information System (INIS)

    Simmons, A.M.

    2004-01-01

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel

  7. YUCCA MOUNTAIN SITE DESCRIPTION

    Energy Technology Data Exchange (ETDEWEB)

    A.M. Simmons

    2004-04-16

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel.

  8. Allogenic sedimentary components of Bear Lake, Utah and Idaho

    Science.gov (United States)

    Rosenbaum, J.G.; Dean, W.E.; Reynolds, R.L.; Reheis, M.C.

    2009-01-01

    Bear Lake is a long-lived lake filling a tectonic depression between the Bear River Range to the west and the Bear River Plateau to the east, and straddling the border between Utah and Idaho. Mineralogy, elemental geochemistry, and magnetic properties provide information about variations in provenance of allogenic lithic material in last-glacial-age, quartz-rich sediment in Bear Lake. Grain-size data from the siliciclastic fraction of late-glacial to Holocene carbonate-rich sediments provide information about variations in lake level. For the quartz-rich lower unit, which was deposited while the Bear River fl owed into and out of the lake, four source areas are recognized on the basis of modern fluvial samples with contrasting properties that reflect differences in bedrock geology and in magnetite content from dust. One of these areas is underlain by hematite-rich Uinta Mountain Group rocks in the headwaters of the Bear River. Although Uinta Mountain Group rocks make up a small fraction of the catchment, hematite-rich material from this area is an important component of the lower unit. This material is interpreted to be glacial fl our. Variations in the input of glacial flour are interpreted as having caused quasi-cyclical variations in mineralogical and elemental concentrations, and in magnetic properties within the lower unit. The carbonate-rich younger unit was deposited under conditions similar to those of the modern lake, with the Bear River largely bypassing the lake. For two cores taken in more than 30 m of water, median grain sizes in this unit range from ???6 ??m to more than 30 ??m, with the coarsest grain sizes associated with beach or shallow-water deposits. Similar grain-size variations are observed as a function of water depth in the modern lake and provide the basis for interpreting the core grain-size data in terms of lake level. Copyright ?? 2009 The Geological Society of America.

  9. Bathymetry of Lake Erie and Lake Saint Clair

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Erie and Lake Saint Clair has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and...

  10. NASA's High Mountain Asia Team (HiMAT): collaborative research to study changes of the High Asia region

    Science.gov (United States)

    Arendt, A. A.; Houser, P.; Kapnick, S. B.; Kargel, J. S.; Kirschbaum, D.; Kumar, S.; Margulis, S. A.; McDonald, K. C.; Osmanoglu, B.; Painter, T. H.; Raup, B. H.; Rupper, S.; Tsay, S. C.; Velicogna, I.

    2017-12-01

    The High Mountain Asia Team (HiMAT) is an assembly of 13 research groups funded by NASA to improve understanding of cryospheric and hydrological changes in High Mountain Asia (HMA). Our project goals are to quantify historical and future variability in weather and climate over the HMA, partition the components of the water budget across HMA watersheds, explore physical processes driving changes, and predict couplings and feedbacks between physical and human systems through assessment of hazards and downstream impacts. These objectives are being addressed through analysis of remote sensing datasets combined with modeling and assimilation methods to enable data integration across multiple spatial and temporal scales. Our work to date has focused on developing improved high resolution precipitation, snow cover and snow water equivalence products through a variety of statistical uncertainty analysis, dynamical downscaling and assimilation techniques. These and other high resolution climate products are being used as input and validation for an assembly of land surface and General Circulation Models. To quantify glacier change in the region we have calculated multidecadal mass balances of a subset of HMA glaciers by comparing commercial satellite imagery with earlier elevation datasets. HiMAT is using these tools and datasets to explore the impact of atmospheric aerosols and surface impurities on surface energy exchanges, to determine drivers of glacier and snowpack melt rates, and to improve our capacity to predict future hydrological variability. Outputs from the climate and land surface assessments are being combined with landslide and glacier lake inventories to refine our ability to predict hazards in the region. Economic valuation models are also being used to assess impacts on water resources and hydropower. Field data of atmospheric aerosol, radiative flux and glacier lake conditions are being collected to provide ground validation for models and remote sensing

  11. Rapid changes in the level of Kluane Lake in Yukon Territory over the last millennium

    Science.gov (United States)

    Clague, John J.; Luckman, Brian H.; Van Dorp, Richard D.; Gilbert, Robert; Froese, Duane; Jensen, Britta J. L.; Reyes, Alberto V.

    2006-09-01

    The level of Kluane Lake, the largest lake in Yukon Territory, was lower than at present during most of the Holocene. The lake rose rapidly in the late seventeenth century to a level 12 m above present, drowning forest and stranding driftwood on a conspicuous high-stand beach, remnants of which are preserved at the south end of the lake. Kluane Lake fell back to near its present level by the end of the eighteenth century and has fluctuated within a range of about 3 m over the last 50 yr. The primary control on historic fluctuations in lake level is the discharge of Slims River, the largest source of water to the lake. We use tree ring and radiocarbon ages, stratigraphy and sub-bottom acoustic data to evaluate two explanations for the dramatic changes in the level of Kluane Lake. Our data support the hypothesis of Hugh Bostock, who suggested in 1969 that the maximum Little Ice Age advance of Kaskawulsh Glacier deposited large amounts of sediment in the Slims River valley and established the present course of Slims River into Kluane Lake. Bostock argued that these events caused the lake to rise and eventually overflow to the north. The overflowing waters incised the Duke River fan at the north end of Kluane Lake and lowered the lake to its present level. This study highlights the potentially dramatic impacts of climate change on regional hydrology during the Little Ice Age in glacierised mountains.

  12. Neotectonic Studies of the Lake Ohrid Basin (FYROM/Albania)

    Science.gov (United States)

    Nadine, H.; Liermann, A.; Glasmacher, U. A.; Reicherter, K. R.

    2010-12-01

    The Lake Ohrid Basin located on 693 m a.s.l. at the south-western border of Macedonia (FYROM) with Albania is a suitable location for neotectonic studies. The lake is set in an extensional basin-and-range-like situation, which is influenced by the roll-back and detachment of the subducted slab of the Northern Hellenic Trench. The seismicity record of the area lists frequent shallow earthquakes with magnitudes of up to 6.6, which classifies the region as one of the highest risk areas for Macedonia and Albania. A multidisciplinary approach was chosen to reveal the stress history of the region. Tectonic morphology, paleostress analysis, remote sensing and geophysical investigations have been taken out to trace the landscape evolution. Furthermore, apatite fission-track (A-FT) analysis and t-T-path modelling was performed to constrain the thermal history and the exhumation rates. The deformation history of the basin can be divided in three major phases. This idea is also supported by paleostress data collected around the lake: 1. NW-SE shortening from Late Cretaceous to Miocene with compression, thrusting and uplift; 2. Uplift and diminishing compression in Late Miocene causing strike-slip and normal faulting; 3. Vertical uplift and E-W extension from Pliocene to present associated with local subsidence and (half-) graben formation. The initiation of the Ohrid Basin can be dated to Late Miocene to Pliocene. The morphology of the basin itself shows features, which characterize the area as an active seismogenic landscape. The elongated NS-trending basin is limited by the steep flanks of Galicica and Mokra Mountains to the E and W, which are tectonically controlled by normal faulting. This is expressed in linear step-like fault scarps on land with heights between 2 and 35 m. The faults have lengths between 10 and 20 km and consist of several segments. Post-glacial bedrock fault scarps at Lake Ohrid are long-lived expressions of repeated surface faulting in tectonically

  13. Extreme ground motions and Yucca Mountain

    Science.gov (United States)

    Hanks, Thomas C.; Abrahamson, Norman A.; Baker, Jack W.; Boore, David M.; Board, Mark; Brune, James N.; Cornell, C. Allin; Whitney, John W.

    2013-01-01

    Yucca Mountain is the designated site of the underground repository for the United States' high-level radioactive waste (HLW), consisting of commercial and military spent nuclear fuel, HLW derived from reprocessing of uranium and plutonium, surplus plutonium, and other nuclear-weapons materials. Yucca Mountain straddles the western boundary of the Nevada Test Site, where the United States has tested nuclear devices since the 1950s, and is situated in an arid, remote, and thinly populated region of Nevada, ~100 miles northwest of Las Vegas. Yucca Mountain was originally considered as a potential underground repository of HLW because of its thick units of unsaturated rocks, with the repository horizon being not only ~300 m above the water table but also ~300 m below the Yucca Mountain crest. The fundamental rationale for a geologic (underground) repository for HLW is to securely isolate these materials from the environment and its inhabitants to the greatest extent possible and for very long periods of time. Given the present climate conditions and what is known about the current hydrologic system and conditions around and in the mountain itself, one would anticipate that the rates of infiltration, corrosion, and transport would be very low—except for the possibility that repository integrity might be compromised by low-probability disruptive events, which include earthquakes, strong ground motion, and (or) a repository-piercing volcanic intrusion/eruption. Extreme ground motions (ExGM), as we use the phrase in this report, refer to the extremely large amplitudes of earthquake ground motion that arise at extremely low probabilities of exceedance (hazard). They first came to our attention when the 1998 probabilistic seismic hazard analysis for Yucca Mountain was extended to a hazard level of 10-8/yr (a 10-4/yr probability for a 104-year repository “lifetime”). The primary purpose of this report is to summarize the principal results of the ExGM research program

  14. Was the 4th largest Danish Lake (Mossø) once much larger?

    DEFF Research Database (Denmark)

    Kristiansen, Søren Munch; Søe, Niels Emil; Kroon, Aart

    actions, antecedent topography and lake level changes on the Holocene development of the present-day Danish lake, Mossø. A variety of methods were used: coring, intensive profile digging and remote sensing, geophysical mapping by seismic reflection and electromagnetic induction, and dating by radiocarbon...

  15. Measuring Dust Emission from the Mojave Desert (USA) by Daily Remote-Camera Observations and Wind-Erosion Measurements: Bearing on "Unseen" Sources and Global Dust Abundance

    Science.gov (United States)

    Reynolds, R. L.; Urban, F.; Goldstein, H. L.; Fulton, R.

    2017-12-01

    A large gap in understanding the effects of atmospheric dust at all spatial scales is uncertainty about how much and whence dust is emitted annually. Digital recording of dust emission at high spatial and temporal resolution would, together with periodic flux measurements, support improved estimates of local-scale dust flux where infrastructure could support remote internet enabled cameras. Such recording would also elucidate wind-erosion dynamics when combined with meteorological data. Remote camera recording of dust-emitting settings on and around Soda Lake (Mojave Desert) was conducted every 15 minutes during daylight between 10 Nov. 2010 and 31 Dec. 2016 and images uploaded to a web server. Examination of 135,000 images revealed frequent dust events, termed "dust days" when plumes obscured mountains beyond source areas. Such days averaged 68 (sd=10) per year (2011 through 2016). We examined satellite retrievals (MODIS, GOES) for dust events during six cloudless days of highest and longest duration dust emission but none were observed. From Apr. 2000 through May 2013, aeolian sediments collected at three sites were sampled and weighed. Estimates of the emitted mass of silt- and clay-size fractions were made on the basis of measured horizontal mass flux, particle sizes of sediment in collectors, and roughly determined areas of dust generation. Over this period, nearly 4 Tg yr-1 of dust (as particulate matter flood in the basin in late Dec. 2010 that deposited flood sediment across the lake basin. Increased emission was likely related to the availability of fresh, unanchored flood sediment. Within the Mojave and Great Basin deserts of North America, many settings akin to those at Soda Lake similarly emit dust that is rarely detected in satellite retrievals. These findings strongly imply that local and regional dust emissions from western North America are far underestimated and that, by extension to relatively small dust-source areas across all drylands, global

  16. Predicting the locations of naturally fishless lakes

    Science.gov (United States)

    Schilling, Emily Gaenzle; Loftin, C.S.; Degoosh, K.E.; Huryn, Alexander D.; Webster, K.E.

    2008-01-01

    1. Fish have been introduced into many previously fishless lakes throughout North America over the past 100+ years. It is difficult to determine the historical distribution of fishless lakes, however, because these introductions have not always been well-documented. 2. Due to its glacial history and low human population density, the state of Maine (U.S.A.) may host the greatest number of naturally fishless lakes in the northeastern United States. However, less than one-quarter of Maine's 6000+ lakes have been surveyed for fish presence, and no accurate assessments of either the historical or current abundance and distribution of fishless lakes exist. 3. We developed methods to assess the abundance and distribution of Maine's naturally fishless lakes (0.6-10.1 ha). We hypothesized that the historical distribution of fishless lakes across a landscape is controlled by geomorphic and geographic conditions. 4. We used ArcGIS to identify landscape-scale geomorphic and geographic factors (e.g. connectivity, surrounding slope) correlated with fish absence in two geomorphic regions of Maine - the western and interior mountains and the eastern lowlands and foothills. By using readily available geographic information systems data our method was not limited to field-visited sites. We estimated the likelihood that a particular lake is fishless with a stepwise logistic regression model developed for each region. 5. The absence of fish from western lakes is related to altitude (+), minimum percent slope in the 500 m buffer (+), maximum percent slope in the 500 m buffer (+) and percent cover of herbaceous-emergent wetland in 1000 m buffer (-). The absence of fish from eastern lakes is related to the lack of a stream within 50 m of the lake. 6. The models predict that a total of 4% (131) of study lakes in the two regions were historically fishless, with the eastern region hosting a greater proportion than the western region. 7. We verified the model predictions with two

  17. The PIRLA project: paleoecological investigations of recent lake acidification

    Energy Technology Data Exchange (ETDEWEB)

    Charles, D F; Whitehead, D R

    1986-12-19

    The PIRLA project is a broadly interdisciplinary paleolimnological investigation of five to fifteen comparable watershed lake systems from each of four low-alkalinity regions in North America that are currently receiving acid deposition. The areas are the Adirondack Mountains (N.Y.), northern New England, northern Great Lakes states, and northern Florida. The primary objective of the study is to provide a detailed reconstruction of the recent acidification histories of a representative suite of lakes from each of the regions. The study will increase our understanding of the timing, rates, and magnitude of acidification (and other chemical changes), and the regional and inter-regional patterns of lake acidification. 3 figs., 2 tabs., 41 refs.

  18. Lake Generated Microseisms at Yellowstone Lake as a Record of Ice Phenology

    Science.gov (United States)

    Mohd Mokhdhari, A. A.; Koper, K. D.; Burlacu, R.

    2017-12-01

    It has recently been shown that wave action in lakes produces microseisms, which generate noise peaks in the period range of 0.8-1.2 s as recorded by nearby seismic stations. Such noise peaks have been observed at seven seismic stations (H17A, LKWY, B208, B944, YTP, YLA, and YLT) located within 2 km of the Yellowstone Lake shoreline. Initial work using 2016 data shows that the variations in the microseism signals at Yellowstone Lake correspond with the freezing and thawing of lake ice: the seismic noise occurs more frequently in the spring, summer, and fall, and less commonly in the winter. If this can be confirmed, then lake-generated microseisms could provide a consistent measure of the freezing and melting dates of high-latitude lakes in remote areas. The seismic data would then be useful in assessing the effects of climate change on the ice phenology of those lakes. In this work, we analyze continuous seismic data recorded by the seven seismic stations around Yellowstone Lake for the years of 1995 to 2016. We generate probability distribution functions of power spectral density for each station to observe the broad elevation of energy near a period of 1 s. The time dependence of this 1-s seismic noise energy is analyzed by extracting the power spectral density at 1 s from every processed hour. The seismic observations are compared to direct measurements of the dates of ice-out and freeze-up as reported by rangers at Yellowstone National Park. We examine how accurate the seismic data are in recording the freezing and melting of Yellowstone Lake, and how the accuracy changes as a function of the number of stations used. We also examine how sensitive the results are to the particular range of periods that are analyzed.

  19. Review Article: Lake and breach hazard assessment for moraine-dammed lakes: an example from the Cordillera Blanca (Peru

    Directory of Open Access Journals (Sweden)

    A. Emmer

    2013-06-01

    Full Text Available Glacial lake outburst floods (GLOFs and related debris flows represent a significant threat in high mountainous areas across the globe. It is necessary to quantify this threat so as to mitigate their catastrophic effects. Complete GLOF hazard assessment incorporates two phases: the probability of water release from a given glacial lake is estimated through lake and breach hazard assessment while the endangered areas are identified during downstream hazard assessment. This paper outlines a number of methods of lake and breach hazard assessment, which can be grouped into three categories: qualitative, of which we outline eight; semi-quantitative, of which we outline two; and quantitative, of which we outline three. It is considered that five groups of critical parameters are essential for an accurate regionally focused hazard assessment method for moraine-dammed lakes in the Cordillera Blanca. These comprise the possibility of dynamic slope movements into the lake, the possibility of a flood wave from a lake situated upstream, the possibility of dam rupture following a large earthquake, the size of the dam freeboard (or ratio of dam freeboard, and a distinction between natural dams and those with remedial work. It is shown that none of the summarised methods uses all these criteria with, at most, three of the five considered by the outlined methods. A number of these methods were used on six selected moraine-dammed lakes in the Cordillera Blanca: lakes Quitacocha, Checquiacocha, Palcacocha, Llaca, Rajucolta, and Tararhua. The results have been compared and show that each method has certain advantages and disadvantages when used in this region. These methods demonstrate that the most hazardous lake is Lake Palcacocha.

  20. Environmental education and technology: using a remotely operated vehicle to connect with nature

    Science.gov (United States)

    Mark Gleason; Laurie Harmon; Kwame Boakye-Agyei

    2007-01-01

    One hundred seven young people (12-14 years old) and 183 adults (25-86 years old) used an underwater remotely operated vehicle (ROV) to explore shipwrecks and marine habitats in the Great Lakes and various inland lakes during the summer of 2005. Content analysis of responses regarding the types of impact the ROV had on their perception and experience with the natural...

  1. Use of microwave remote sensing in salinity estimation

    International Nuclear Information System (INIS)

    Singh, R.P.; Kumar, V.; Srivastav, S.K.

    1990-01-01

    Soil-moisture interaction and the consequent liberation of ions causes the salinity of waters. The salinity of river, lake, ocean and ground water changes due to seepage and surface runoff. We have studied the feasibility of using microwave remote sensing for the estimation of salinity by carrying out numerical calculations to study the microwave remote sensing responses of various models representative of river, lake and ocean water. The results show the dependence of microwave remote sensing responses on the salinity and surface temperature of water. The results presented in this paper will be useful in the selection of microwave sensor parameters and in the accurate estimation of salinity from microwave remote sensing data

  2. Modes of supraglacial lake drainage and dynamic ice sheet response

    Science.gov (United States)

    Das, S. B.; Behn, M. D.; Joughin, I. R.

    2011-12-01

    We investigate modes of supraglacial lake drainage using geophysical, ground, and remote sensing observations over the western margin of the Greenland ice sheet. Lakes exhibit a characteristic life cycle defined by a pre-drainage, drainage, and post-drainage phase. In the pre-drainage phase winter snow fills pre-existing cracks and stream channels, efficiently blocking past drainage conduits. As temperatures increase in the spring, surface melting commences, initially saturating the snow pack and subsequently forming a surface network of streams that fills the lake basins. Basins continue to fill until lake drainage commences, which for individual lakes occurs at different times depending on the previous winter snow accumulation and summer temperatures. Three styles of drainage behavior have been observed: (1) no drainage, (2) slow drainage over the side into an adjacent pre-existing crack, and (3) rapid drainage through a new crack formed beneath the lake basin. Moreover, from year-to-year individual lakes exhibit different drainage behaviors. Lakes that drain slowly often utilize the same outflow channel for multiple years, creating dramatic canyons in the ice. Ultimately, these surface channels are advected out of the lake basin and a new channel forms. In the post-drainage phase, melt water continues to access the bed typically through a small conduit (e.g. moulin) formed near a local topographic minimum along the main drainage crack, draining the lake catchment throughout the remainder of the melt season. This melt water input to the bed leads to continued basal lubrication and enhanced ice flow compared to background velocities. Lakes that do not completely drain freeze over to form a surface ice layer that persists into the following year. Our results show that supraglacial lakes show a spectrum of drainage behaviors and that these styles of drainage lead to varying rates and timing of surface meltwater delivery to the bed resulting in different dynamic ice

  3. Mountain Biking Injuries.

    Science.gov (United States)

    Ansari, Majid; Nourian, Ruhollah; Khodaee, Morteza

    With the increasing popularity of mountain biking, also known as off-road cycling, and the riders pushing the sport into extremes, there has been a corresponding increase in injury. Almost two thirds of acute injuries involve the upper extremities, and a similar proportion of overuse injuries affect the lower extremities. Mountain biking appears to be a high-risk sport for severe spine injuries. New trends of injury patterns are observed with popularity of mountain bike trail parks and freeride cycling. Using protective gear, improving technical proficiency, and physical fitness may somewhat decrease the risk of injuries. Simple modifications in bicycle-rider interface areas and with the bicycle (bike fit) also may decrease some overuse injuries. Bike fit provides the clinician with postural correction during the sport. In this review, we also discuss the importance of race-day management strategies and monitoring the injury trends.

  4. Investigating potential effects of heli-skiing on golden eagles in the Wasatch Mountains, Utah

    Science.gov (United States)

    Teryl G. Grubb; David K. Delaney; William W. Bowerman

    2007-01-01

    Implementing further research was beyond the scope of the U.S. Forest Service's 2004 Final Environmental Impact Statement (FEIS) and 2005 Wasatch Powderbird Guides (WPG) Special Use Permit Renewal process for heli-skiing in the Tri-Canyon Area in the Wasatch Mountains, just east of Salt Lake City, Utah. However, in their Record of Decision the Wasaatch-Cache (WCNF...

  5. Lake or Pond WBID

    Data.gov (United States)

    Vermont Center for Geographic Information — The VT DEC (Vermont Department of Environmental Conservation) manages an inventory of lake and pond information. The "Lakes and Ponds Inventory" stores the Water...

  6. National Lakes Assessment Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — The National Lakes Assessment (NLA) is a first-ever statistically-valid survey of the biological condition of lakes and reservoirs throughout the U.S. The U.S....

  7. DNR 24K Lakes

    Data.gov (United States)

    Minnesota Department of Natural Resources — Medium scale lake polygons derived from the National Wetlands Inventory (NWI) polygons and MnDOT Basemap lake delineations. Integrated with the DNR 24K Streams...

  8. Eruptive behavior of the Marum/Mbwelesu lava lake, Vanuatu and comparisons with lava lakes on Earth and Io

    Science.gov (United States)

    Radebaugh, Jani; Lopes, Rosaly M.; Howell, Robert R.; Lorenz, Ralph D.; Turtle, Elizabeth P.

    2016-08-01

    Observations from field remote sensing of the morphology, kinematics and temperature of the Marum/Mbwelesu lava lake in the Vanuatu archipelago in 2014 reveal a highly active, vigorously erupting lava lake. Active degassing and fountaining observed at the 50 m lava lake led to large areas of fully exposed lavas and rapid ( 5 m/s) movement of lava from the centers of upwelling outwards to the lake margins. These rapid lava speeds precluded the formation of thick crust; there was never more than 30% non-translucent crust. The lava lake was observed with several portable, handheld, low-cost, near-infrared imagers, all of which measured temperatures near 1000 °C and one as high as 1022 °C, consistent with basaltic temperatures. Fine-scale structure in the lava fountains and cooled crust was visible in the near infrared at 5 cm/pixel from 300 m above the lake surface. The temperature distribution across the lake surface is much broader than at more quiescent lava lakes, peaking 850 °C, and is attributed to the highly exposed nature of the rapidly circulating lake. This lava lake has many characteristics in common with other active lava lakes, such as Erta Ale in Ethiopia, being confined, persistent and high-temperature; however it was much more active than is typical for Erta Ale, which often has > 90% crust. Furthermore, it is a good analogue for the persistent, high-temperature lava lakes contained within volcanic depressions on Jupiter's moon Io, such as Pele, also believed from spacecraft and ground-based observations to exhibit similar behavior of gas emission, rapid overturn and fountaining.

  9. Environmental exposures to agrochemicals in the Sierra Nevada mountain range

    Science.gov (United States)

    LeNoir, J.; Aston, L.; Data, S.; Fellers, G.; McConnell, L.; Sieber, J.

    2000-01-01

    The release of pesticides into the environment may impact human and environmental health. Despite the need for environmental exposure data, few studies quantify exposures in urban areas and even fewer determine exposures to wildlife in remote areas. Although it is expected that concentrations in remote regions will be low, recent studies suggest that even low concentrations may have deleterious effects on wildlife. Many pesticides are known to interfere with the endocrine systems of humans and wildlife, adversely affecting growth, development, and behavior. This chapter reviews the fate and transport of pesticides applied in the Central Valley of California and quantifies their subsequent deposition into the relatively pristine Sierra Nevada Mountain Range.

  10. Generating High-Resolution Lake Bathymetry over Lake Mead using the ICESat-2 Airborne Simulator

    Science.gov (United States)

    Li, Y.; Gao, H.; Jasinski, M. F.; Zhang, S.; Stoll, J.

    2017-12-01

    Precise lake bathymetry (i.e., elevation/contour) mapping is essential for optimal decision making in water resources management. Although the advancement of remote sensing has made it possible to monitor global reservoirs from space, most of the existing studies focus on estimating the elevation, area, and storage of reservoirs—and not on estimating the bathymetry. This limitation is attributed to the low spatial resolution of satellite altimeters. With the significant enhancement of ICESat-2—the Ice, Cloud & Land Elevation Satellite #2, which is scheduled to launch in 2018—producing satellite-based bathymetry becomes feasible. Here we present a pilot study for deriving the bathymetry of Lake Mead by combining Landsat area estimations with airborne elevation data using the prototype of ICESat-2—the Multiple Altimeter Beam Experimental Lidar (MABEL). First, an ISODATA classifier was adopted to extract the lake area from Landsat images during the period from 1982 to 2017. Then the lake area classifications were paired with MABEL elevations to establish an Area-Elevation (AE) relationship, which in turn was applied to the classification contour map to obtain the bathymetry. Finally, the Lake Mead bathymetry image was embedded onto the Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM), to replace the existing constant values. Validation against sediment survey data indicates that the bathymetry derived from this study is reliable. This algorithm has the potential for generating global lake bathymetry when ICESat-2 data become available after next year's launch.

  11. Lakes near the glacier Maliy Azau on the Elbrus (Central Caucasus: dynamics and outbursts

    Directory of Open Access Journals (Sweden)

    M. D. Dokukin

    2016-01-01

    Full Text Available The lake dynamics and the current state of them were analyzed on the basis of interpretation of aerial and satellite images of different years together with results of field surveys. Areas of six lakes existing in different years near the Maliy Azau Glacier had been determined. On August 22, 2011, the maximum area of one of the lakes was equal to 25.5 thousand m2. The first outburst was caused by the landslide deformations of the moraine massif forming a part of the lake basin, while the second one was a result of degradation of the lake ice dam and the water overflow on top of it. The present‑day lake dams (terminal‑moraine ramparts and medial moraine ridges are the result of the Maliy Azau Glacier advance in 1990s. The revealed feature of the lake dynamics on the mountain Elbrus was a drop of the water level and corresponding decrease of the lake areas in winter that was related to existence of the groundwater runoff into fractured volcanic rocks. At present, moraine dams of lakes and areas of the surface water runoff from the lakes are in stable condition due to which there is no threat of a lake outburst. However, the potential threat of outburst still remains because of high seismicity and possible volcanic activity in this region.

  12. Chemical composition of the Tatra Mountain lakes: Response to acidification

    Czech Academy of Sciences Publication Activity Database

    Stuchlík, E.; Kopáček, Jiří; Fott, J.; Hořická, Z.

    2006-01-01

    Roč. 61, Suppl. 18 (2006), S11-S20 ISSN 0006-3088 Grant - others:EC(XE) GOCE-CT-2003-505540; EC(XE) EV5V-CT92-0205 Institutional research plan: CEZ:AV0Z60170517 Keywords : acidification * long-term trends * nutrients Subject RIV: DJ - Water Pollution ; Quality Impact factor: 0.213, year: 2006

  13. The Olympic Mountains Experiment for GPM (OLYMPEX)

    Science.gov (United States)

    Houze, R.; McMurdie, L. A.; Petersen, W. A.; Schwaller, M.

    2016-12-01

    The GPM satellite has made it possible to observe the amount and nature of precipitation in remote areas of midlatitudes, including oceans and mountain ranges. OLYMPEX conducted over the Olympic Mountains on the northwest coast of Washington State was designed to provide the means for evaluating the physical basis of the algorithms used to convert GPM satellite measurements to determine the amount and nature of precipitation in midlatitude extratropical cyclones. Microphysical processes producing precipitation are highly sensitive to the vertical profile of temperature. In the tropics, the domain of the TRMM satellite, the temperature profile varies only slightly. GPM algorithms, however, must account for the strong horizontal variation of temperature profiles in baroclinic storms systems of midlatitudes and for the variations of precipitation mechanisms caused by passage of these storms over mountains. The OLYMPEX scientific strategy was: 1) collect a statistically robust set of measurements in midlatitude cyclones upstream of, over, and downstream of a midlatitude mountain range that can be used to improve GPM satellite algorithms; 2) determine how the physics and dynamics of the mechanisms affecting precipitation formation in relation to storm structure and terrain. To accomplish these goals 3 aircraft, 4 scanning dual polarization Doppler radars, supplemental soundings, and sophisticated surface instruments were deployed on the Olympic Peninsula of Washington, where Pacific frontal systems produce seasonal precipitation of 2000-4000 mm. 13 storms were observed. 3 of these were atmospheric rivers. The NASA DC-8 and ER-2 aircraft overflew the storms with instruments similar to those on GPM. The U. North Dakota Citation sampled hydrometeors in situ. Preliminary analysis indicates that one of the primary modes of orographic enhancement is low-level moist flow rising over the lower windward slopes and producing many very small drops. Ice-phase processes producing

  14. Botanical Provenance of Traditional Medicines From Carpathian Mountains at the Ukrainian-Polish Border

    OpenAIRE

    Weronika Kozlowska; Charles Wagner; Charles Wagner; Erin M. Moore; Erin M. Moore; Adam Matkowski; Slavko Komarnytsky; Slavko Komarnytsky

    2018-01-01

    Plants were an essential part of foraging for food and health, and for centuries remained the only medicines available to people from the remote mountain regions. Their correct botanical provenance is an essential basis for understanding the ethnic cultures, as well as for chemical identification of the novel bioactive molecules with therapeutic effects. This work describes the use of herbal medicines in the Beskid mountain ranges located south of Krakow and Lviv, two influential medieval cen...

  15. Community Dynamics and Soil Seed Bank Ecology of Lane Mountain Milkvetch (Astragalus jaegerianus Munz)

    Science.gov (United States)

    2012-08-01

    concentrated in four geographic areas (Coolgardie Mesa, Paradise Valley, Brinkman Wash-Montana Mine , and the Gemini Conservation Area; Fig. 1) that total...data for 2003, and from 2007 through 2009 were generated by the remote automated weather station (RAWS) at Opal Mountain CA (35°09´N; 117°10´W; 980...m.). This weather station is approximately 30 km SW of UCLA’s milkvetch study sites. Opal Mountain and Goldstone monthly precipitation from 1992

  16. Water Surface Overgrowing of the Tatra’s Lakes

    Directory of Open Access Journals (Sweden)

    Kapusta Juraj

    2018-03-01

    Full Text Available Tatra’s lakes are vulnerable ecosystems and an important element of the alpine landscape. Mainly some shallow lake basins succumb to intense detritus sedimentation, fine fractions of material from the catchment area or to the overgrowing of water level by vegetation. In this paper, changes and dynamics of the 12 Tatra’s lake shorelines that were selected based on the detailed mapping of their extent are pointed out. Changes were assessed by accurate comparisons of historical and current orthophoto maps from the years 1949, 1955 and 2015 – and therefore, based on the oldest and the latest relevant materials. Due to the overgrowing of lakes caused by vegetation, their water surface decreased from −0.9% up to −47.9%, during the examined period. Losses were caused by the overgrowing of open water surface by the communities of sedges and peat bogs. The most significant dynamics of the shorelines during the last decades were reached by those lakes, into which fine sediments were simultaneously deposited by means of mountain water coarse. These sediments made the marginal parts of the lake basins shallower and accelerated rapid expansion of vegetation to the detriment of the open water surface. The overgrowing of shallow moraine lakes lying in the vegetation zone is a significant phenomenon of the High Tatras alpine landscape. It leads to their gradual extinction, turn into peat bogs and wet alpine meadows.

  17. Mountain-Plains Curriculum.

    Science.gov (United States)

    Mountain-Plains Education and Economic Development Program, Inc., Glasgow AFB, MT.

    The document lists the Mountain-Plains curriculum by job title (where applicable), including support courses. The curriculum areas covered are mathematics skills, communication skills, office education, lodging services, food services, marketing and distribution, welding support, automotive, small engines, career guidance, World of Work, health…

  18. Injuries in mountain biking.

    Science.gov (United States)

    Gaulrapp, H; Weber, A; Rosemeyer, B

    2001-01-01

    Despite still growing attraction mountain biking as a matter of sports traumatology still lacks relevant data based on large cross-sectional surveys. To obtain an overview of risk factors, types, and main body sites of injuries occurring in mountain biking we assessed the results of a questionnaire answered by 3873 athletes. A total of 8133 single lesions were reported by 3474 athletes, 36% of whom regularly participated in competitions. The incidence of injuries in mountain biking is comparable to that in other outdoor sports, the majority of injuries being minor. Mountain biking athletes were found to have an overall injury risk rate of 0.6% per year and 1 injury per 1000 h of biking. The main risk factors included slippery road surface, cyclist's poor judgement of the situation, and excessive speed, representing personal factors that could be altered by preventive measures. Of all injuries 14% were due to collision with some part of the bike, especially the pedals and the handlebar. While 75% of the injuries were minor, such as skin wounds and simple contusions, 10% were so severe that hospitalization was required. A breakdown of the injuries according to body site and frequency of occurrence is presented.

  19. Rocky Mountain High.

    Science.gov (United States)

    Hill, David

    2001-01-01

    Describes Colorado's Eagle Rock School, which offers troubled teens a fresh start by transporting them to a tuition- free campus high in the mountains. The program encourages spiritual development as well as academic growth. The atmosphere is warm, loving, structured, and nonthreatening. The article profiles several students' experiences at the…

  20. The ESA River & Lake System: Current Capabilities and Future Potential

    DEFF Research Database (Denmark)

    Smith, Richard G.; Salloway, Mark; Berry, Philippa A. M.

    Measuring the earth's river and lake resources using satellite radar altimetry offers a unique global monitoring capability, which complements the detailed measurements made by the steadily decreasing number of in-situ gauges. To exploit this unique remote monitoring capability, a global pilot...

  1. Reconstructing Heat Fluxes Over Lake Erie During the Lake Effect Snow Event of November 2014

    Science.gov (United States)

    Fitzpatrick, L.; Fujisaki-Manome, A.; Gronewold, A.; Anderson, E. J.; Spence, C.; Chen, J.; Shao, C.; Posselt, D. J.; Wright, D. M.; Lofgren, B. M.; Schwab, D. J.

    2017-12-01

    The extreme North American winter storm of November 2014 triggered a record lake effect snowfall (LES) event in southwest New York. This study examined the evaporation from Lake Erie during the record lake effect snowfall event, November 17th-20th, 2014, by reconstructing heat fluxes and evaporation rates over Lake Erie using the unstructured grid, Finite-Volume Community Ocean Model (FVCOM). Nine different model runs were conducted using combinations of three different flux algorithms: the Met Flux Algorithm (COARE), a method routinely used at NOAA's Great Lakes Environmental Research Laboratory (SOLAR), and the Los Alamos Sea Ice Model (CICE); and three different meteorological forcings: the Climate Forecast System version 2 Operational Analysis (CFSv2), Interpolated observations (Interp), and the High Resolution Rapid Refresh (HRRR). A few non-FVCOM model outputs were also included in the evaporation analysis from an atmospheric reanalysis (CFSv2) and the large lake thermodynamic model (LLTM). Model-simulated water temperature and meteorological forcing data (wind direction and air temperature) were validated with buoy data at three locations in Lake Erie. The simulated sensible and latent heat fluxes were validated with the eddy covariance measurements at two offshore sites; Long Point Lighthouse in north central Lake Erie and Toledo water crib intake in western Lake Erie. The evaluation showed a significant increase in heat fluxes over three days, with the peak on the 18th of November. Snow water equivalent data from the National Snow Analyses at the National Operational Hydrologic Remote Sensing Center showed a spike in water content on the 20th of November, two days after the peak heat fluxes. The ensemble runs presented a variation in spatial pattern of evaporation, lake-wide average evaporation, and resulting cooling of the lake. Overall, the evaporation tended to be larger in deep water than shallow water near the shore. The lake-wide average evaporations

  2. A critical review of the development, current hotspots, and future directions of Lake Taihu research from the bibliometrics perspective.

    Science.gov (United States)

    Zhang, Yunlin; Yao, Xiaolong; Qin, Boqiang

    2016-07-01

    Lake Taihu, as the important drinking water source of the Yangtze River Delta urban agglomeration and the third largest freshwater lake in China, has experienced serious lake eutrophication and water quality deterioration in the past three decades. Growing scientific, political, and public attention has been given to the water quality of Lake Taihu. This study aimed to conduct a comparative quantitative and qualitative analysis of the development, current hotspots, and future directions of Lake Taihu research using a bibliometric analysis of eight well-studied lakes (Lake Taihu, Lake Baikal, Lake Biwa, Lake Erie, Lake Michigan, Lake Ontario, Lake Superior and Lake Victoria) around the world based on the Science Citation Index (SCI) database. A total of 1582 papers discussing Lake Taihu research were published in 322 journals in the past three decades. However, the first paper about Lake Taihu research was not found in the SCI database until 1989, and there were only zero, one, or two papers each year from 1989 to 1995. There had been rapid development in Lake Taihu research since 1996 and a sharp increase in papers since 2005. A keyword analysis showed that "sediment," "eutrophication", "Microcystis aeruginosa", "cyanobacterial blooms", and "remote sensing" were the most frequently used keywords of the study subject. Owing to its significant impact on aquatic ecosystems, a crucial emphasis has been placed on climate change recently. In addition, the future focuses of research directions, including (1) environmental effects of physical processes; (2) nutrient cycles and control and ecosystem responses; (3) cyanobacteria bloom monitoring, causes, forecast and management; (4) eutrophication and climate change interactions; and (5) ecosystem degradation mechanism and ecological practice of lake restoration, are presented based on the keyword analysis. Through multidisciplinary fields (physics, chemistry, and biology) cross and synthesis study of Lake Taihu, the

  3. Late Quaternary sedimentary features of Bear Lake, Utah and Idaho

    Science.gov (United States)

    Smoot, J.P.

    2009-01-01

    Bear Lake sediments were predominantly aragonite for most of the Holocene, reflecting a hydrologically closed lake fed by groundwater and small streams. During the late Pleistocene, the Bear River flowed into Bear Lake and the lake waters spilled back into the Bear River drainage. At that time, sediment deposition was dominated by siliciclastic sediment and calcite. Lake-level fluctuation during the Holocene and late Pleistocene produced three types of aragonite deposits in the central lake area that are differentiated primarily by grain size, sorting, and diatom assemblage. Lake-margin deposits during this period consisted of sandy deposits including well-developed shoreface deposits on margins adjacent to relatively steep gradient lake floors and thin, graded shell gravel on margins adjacent to very low gradient lake-floor areas. Throughout the period of aragonite deposition, episodic drops in lake level resulted in erosion of shallow-water deposits, which were redeposited into the deeper lake. These sediment-focusing episodes are recognized by mixing of different mineralogies and crystal habits and mixing of a range of diatom fauna into poorly sorted mud layers. Lake-level drops are also indicated by erosional gaps in the shallow-water records and the occurrence of shoreline deposits in areas now covered by as much as 30 m of water. Calcite precipitation occurred for a short interval of time during the Holocene in response to an influx of Bear River water ca. 8 ka. The Pleistocene sedimentary record of Bear Lake until ca. 18 ka is dominated by siliciclastic glacial fl our derived from glaciers in the Uinta Mountains. The Bear Lake deep-water siliciclastic deposits are thoroughly bioturbated, whereas shallow-water deposits transitional to deltas in the northern part of the basin are upward-coarsening sequences of laminated mud, silt, and sand. A major drop in lake level occurred ca. 18 ka, resulting in subaerial exposure of the lake floor in areas now covered by

  4. Mountains: top down.

    Science.gov (United States)

    Woodwell, George M

    2004-11-01

    Mountainous regions offer not only essential habitat and resources, including water, to the earth's more than 6 billion inhabitants, but also insights into how the global human habitat works, how it is being changed at the moment as global climates are disrupted, and how the disruption may lead to global biotic and economic impoverishment. At least 600 million of the earth's more than 6 billion humans dwell in mountainous regions. Such regions feed water into all the major rivers of the world whose valleys support most of the rest of us. At least half of the valley dwellers receive part or all of their water from montane sources, many from the melt water of glaciers, others from the annual snow melt. Glaciers are retreating globally as the earth warms as a result of human-caused changes in the composition of the atmosphere. Many are disappearing, a change that threatens municipal water supplies virtually globally. The warming is greatest in the higher latitudes where the largest glaciers such as those of Greenland and the Antarctic Continent have become vulnerable. The melting of ice in the northern hemisphere raises serious concerns about the continued flow of the Gulf Stream and the possibility of massive climatic changes in Scandinavia and northern Europe. Mountains are also biotic islands in the sea life, rich in endemism at the ecotype level. The systematic warming of the earth changes the environment out from under these genetically specialized strains (ecotypes) which are then maladapted and vulnerable to diseases of all types. The process is systematic impoverishment in the pattern conspicuous on mountain slopes with increasing exposure to climatic extremes. It is seen now in the increased mortality and morbidity of plants as climatic changes accumulate. The seriousness of the global climatic disruption is especially clear in any consideration of mountains. It can and must be addressed constructively despite the adamancy of the current US administration.

  5. Snowmelt timing, phenology, and growing season length in conifer forests of Crater Lake National Park, USA

    Science.gov (United States)

    O'Leary, Donal S.; Kellermann, Jherime L.; Wayne, Chris

    2018-02-01

    Anthropogenic climate change is having significant impacts on montane and high-elevation areas globally. Warmer winter temperatures are driving reduced snowpack in the western USA with broad potential impacts on ecosystem dynamics of particular concern for protected areas. Vegetation phenology is a sensitive indicator of ecological response to climate change and is associated with snowmelt timing. Human monitoring of climate impacts can be resource prohibitive for land management agencies, whereas remotely sensed phenology observations are freely available at a range of spatiotemporal scales. Little work has been done in regions dominated by evergreen conifer cover, which represents many mountain regions at temperate latitudes. We used moderate resolution imaging spectroradiometer (MODIS) data to assess the influence of snowmelt timing and elevation on five phenology metrics (green up, maximum greenness, senescence, dormancy, and growing season length) within Crater Lake National Park, Oregon, USA from 2001 to 2012. Earlier annual mean snowmelt timing was significantly correlated with earlier onset of green up at the landscape scale. Snowmelt timing and elevation have significant explanatory power for phenology, though with high variability. Elevation has a moderate control on early season indicators such as snowmelt timing and green up and less on late-season variables such as senescence and growing season length. PCA results show that early season indicators and late season indicators vary independently. These results have important implications for ecosystem dynamics, management, and conservation, particularly of species such as whitebark pine ( Pinus albicaulis) in alpine and subalpine areas.

  6. A hypocystal archeopyle in a freshwater dinoflagellate from the Peridinium umbonatum group (Dinophyceae) from Lake Nero di Cornisello, South Eastern Alps, Italy

    DEFF Research Database (Denmark)

    Tardio, Massimiliano; Ellegaard, Marianne; Lundholm, Nina

    2009-01-01

    Cornisello, a low-alkalinity high mountain lake of the Adamello mountain range (2233m above sea level, South Eastern Alps, Italy). The archeopyle is large, clearly hypocystal, polygonal, and slightly peanut-shaped. The species producing this cyst belongs to the Peridinium umbonatum group and is described...

  7. The primary opinion on the formation mechanisms of mega dunes and lakes in the Badain jaran desert

    International Nuclear Information System (INIS)

    Guo Yonghai; Li Yawei

    2010-01-01

    Badain Jaran Desert is famous in distribution of many lakes and mega dunes in the world. Up to now, there are several different opinions about formation problems of lakes and mega dunes. Actually, these problems are directly correlated to the groundwater circulation and alternation in the area. Refering to the prevenient research results and combining with the current hydrogeological investigation in the desert, the paper discussed the problems about the formation mechanisms of lakes and mega dunes. The Primary cognition is that: the lakes in the desert were formed mainly by the lateral recharge of groundwaters both from Yabulai mountain and mega dunes. The formation of the mega dunes was related nearly to the rainfall and groundwater in the area. The formation and coexistence relationship between lakes and mega dunes is that: the mega dunes were formed firstly, and then the lakes. That is to say the mega dunes are the basic conditions for the lake formation. (authors)

  8. The impact of free convection on late morning ozone decreases on an Alpine foreland mountain summit

    Directory of Open Access Journals (Sweden)

    J.-C. Mayer

    2008-10-01

    Full Text Available Exceptional patterns in the diurnal course of ozone mixing ratio at a mountain top site (998 m a.s.l. were observed during a field experiment (September 2005. They manifested themselves as strong and sudden decreases of ozone mixing ratio with a subsequent return to previous levels. The evaluation of corresponding long-term time series (2000–2005 revealed that such events occur mainly during summer, and affect the mountain top site on about 18% of the summer days. Combining (a surface layer measurements at mountain summit and at the foot of the mountain, (b in-situ (tethered balloon and remote sensing (SODAR-RASS measurements within the atmospheric boundary layer, the origin of these events of sudden ozone decrease could be attributed to free convection. The free convection was triggered by a rather frequently occurring wind speed minimum around the location of the mountain.

  9. Aerobic biodegradation potential of endocrine disrupting chemicals in surface-water sediment at Rocky Mountains National Park, USA

    Science.gov (United States)

    Bradley, Paul M.; Battaglin, William A.; Iwanowicz, Luke R.; Clark, Jimmy M.; Journey, Celeste A.

    2016-01-01

    Endocrine disrupting chemicals (EDC) in surface water and bed sediment threaten the structure and function of aquatic ecosystems. In natural, remote, and protected surface-water environments where contaminant releases are sporadic, contaminant biodegradation is a fundamental driver of exposure concentration, timing, duration, and, thus, EDC ecological risk. Anthropogenic contaminants, including known and suspected EDC, were detected in surface water and sediment collected from 2 streams and 2 lakes in Rocky Mountains National Park (ROMO). The potential for aerobic EDC biodegradation was assessed in collected sediments using 6 14C-radiolabeled model compounds. Aerobic microbial mineralization of natural (estrone and 17β-estradiol) and synthetic (17α-ethinylestradiol) estrogen was significant at all sites. ROMO bed sediment microbial communities also effectively degraded the xenoestrogens, bisphenol-A and 4-nonylphenol. The same sediment samples exhibited little potential for aerobic biodegradation of triclocarban, however, illustrating the need to assess a wider range of contaminant compounds. The current results support recent concerns over the widespread environmental occurrence of carbanalide antibacterials, like triclocarban and triclosan, and suggest that backcountry use of products containing these compounds should be discouraged.

  10. Characteristics and sources of chromophoric dissolved organic matter in lakes of the Yungui Plateau, China, differing in trophic state and altitude

    NARCIS (Netherlands)

    Zhang, Y.; Zhang, E.; Yin, Y.; Van Dijk, M.A.; Feng, L.; Shi, Z.; Liu, M.; Qina, B.

    2010-01-01

    The high-mountain lakes on the Yungui Plateau in China are exposed to high-intensity ultraviolet radiation, and contain low concentrations of chromophoric dissolved organic matter (CDOM). We determined CDOM absorption, fluorescence, composition, and source in 38 lakes on the Yungui Plateau at

  11. A Conceptual Model for Remote Data Acquisition Using SMSLib ...

    African Journals Online (AJOL)

    This paper presents a design of a remote lake-water-level measurement data acquisition system via UMTS network. The system accomplishes the function of data processing and transmitting by the use of SMSlib software and a java application developed. A tree layer system is designed to achieve this work: a mobile ...

  12. Waste management outlook for mountain regions: Sources and solutions.

    Science.gov (United States)

    Semernya, Larisa; Ramola, Aditi; Alfthan, Björn; Giacovelli, Claudia

    2017-09-01

    Following the release of the global waste management outlook in 2015, the United Nations Environment Programme (UN Environment), through its International Environmental Technology Centre, is elaborating a series of region-specific and thematic waste management outlooks that provide policy recommendations and solutions based on current practices in developing and developed countries. The Waste Management Outlook for Mountain Regions is the first report in this series. Mountain regions present unique challenges to waste management; while remoteness is often associated with costly and difficult transport of waste, the potential impact of waste pollutants is higher owing to the steep terrain and rivers transporting waste downstream. The Outlook shows that waste management in mountain regions is a cross-sectoral issue of global concern that deserves immediate attention. Noting that there is no 'one solution fits all', there is a need for a more landscape-type specific and regional research on waste management, the enhancement of policy and regulatory frameworks, and increased stakeholder engagement and awareness to achieve sustainable waste management in mountain areas. This short communication provides an overview of the key findings of the Outlook and highlights aspects that need further research. These are grouped per source of waste: Mountain communities, tourism, and mining. Issues such as waste crime, plastic pollution, and the linkages between exposure to natural disasters and waste are also presented.

  13. Challenges and uncertainties in hydrological modelling of remote Hindu Kush-Himalayan (HKH) basins: suggestions for calibration strategies

    NARCIS (Netherlands)

    Pellicciotti, F.; Konz, M.; Immerzeel, W.W.; Shresta, A.B.

    2012-01-01

    Assessment of water resources from remote mountainous catchments plays a crucial role for the development of rural areas in or in the vicinity of mountain ranges. The scarcity of data, however, prevents the application of standard approaches that are based on data-driven models. The Hindu

  14. Remote possibilities

    International Nuclear Information System (INIS)

    Fernandes, J.

    1995-01-01

    The impact that wireless communications has had for gas and oil producers was discussed. Wireless communication, which has been replacing the traditional formats of radio and telephone data networks, has proved to be cheaper, smaller, and faster than creating privately owned communication networks. With highly developed supervisory control and data acquisition systems - combined with cellular or satellite technology - information from drill sites can be online at the corporate headquarters instantaneously. Eighty percent of Canada's land mass is beyond reach of traditional wireline and wireless services. Research into advanced communications, including telecommunication and mobile applications, yielded lucrative results for service providers such as BCTel, SaskTel, Bell Mobility and AGT. The latest data transmission technology is the cellular digital packet data (CDPD) which will operate over existing cellular networks. However, unlike circuit-switched cellular, CDPD technology provides an airlink where data is secure. It will be available to the marketplace over the course of the coming year. Among other advantages, CDPD will allow producers to remotely monitor production information and downtime alarms from wells and compressor stations. It will also provide fleet operators with the means to monitor operating vital signs on rolling stock

  15. Assessment of glacial lake development and prospects of outburst susceptibility: Chamlang South Glacier, eastern Nepal Himalaya

    Directory of Open Access Journals (Sweden)

    Damodar Lamsal

    2016-01-01

    Full Text Available Chamlang South Tsho has been identified as one of the six high-priority glacial lakes in terms of glacial lake outburst flood (GLOF danger in Nepal Himalaya, despite the fact that no detailed investigations of the lake had been hitherto undertaken. We conducted detailed mapping of the lake and its surroundings along with field surveys in October 2009 to determine the developmental history of Chamlang South Tsho and to assess its potential for GLOF. The lake expanded rapidly between 1964 (0.04 km2 and 2000 (0.86 km2 and has been stable ever since. Future lake expansion is improbable as its sides are confined by relatively stable landforms. The lake is 87-m deep with a water volume of approximately 34.9–35.6 × 106 m3. Hanging glaciers on the steep surrounding mountain slopes and prominent seepage water in the terminal moraine dam could be potential triggers for a future outburst flood. Additionally, the debris-covered dead-ice dam, which is higher than the lake water level, is narrow and low; therefore, it could be overtopped easily by surge waves. Furthermore, the pronounced difference in elevation between the lake and the base of the terminal moraine dam makes the lake susceptible for a large flood.

  16. Western Alaska ESI: LAKES (Lake Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing lakes and land masses used in the creation of the Environmental Sensitivity Index (ESI) for Western Alaska. The...

  17. DOE's Yucca Mountain studies

    International Nuclear Information System (INIS)

    1992-12-01

    This booklet is about the disposal of high-level nuclear waste in the United States. It is for readers who have a general rather than a technical background. It discusses why scientists and engineers thinkhigh-level nuclear waste may be disposed of safely underground. It also describes why Yucca Mountain, Nevada, is being studied as a potential repository site and provides basic information about those studies

  18. Yucca Mountain Milestone

    International Nuclear Information System (INIS)

    Hunt, Rod

    1997-01-01

    The Department of Energy project to determine if the Yucca Mountain site in Nevada is suitable for geologic disposal of high-level nuclear waste reached a major milestone in late April when a 25-foot-diameter tunnel boring machine ''holed through'' completing a five-mile-long, horseshoe-shaped excavation through the mountain. When the cutting-head of the giant machine broke through to daylight at the tunnel's south portal, it ended a 2 1/2-year excavation through the mountain that was completed ahead of schedule and with an outstanding safety record. Video of the event was transmitted live by satellite to Washington, DC, where it was watched by Secretary of Energy Frederico Pena and other high-level DOE officials, signifying the importance of the project's mission to find a repository for high-level nuclear waste and spent nuclear fuel produced by nuclear power plants. This critical undertaking is being performed by DOE's Office of Civilian Radioactive Waste Management (OCRWM). The tunnel is the major feature of the Exploratory Studies Facility (ESF), which serves as an underground laboratory for engineers and scientists to help determine if Yucca Mountain is suitable to serve as a repository for the safe disposal of high-level nuclear waste. Morrison Knudsen's Environmental/Government Group is providing design and construction-management services on the project. The MK team is performing final design for the ESF and viability assessment design for the underground waste repository that will be built only if the site is found suitable for such a mission. In fact, if at anytime during the ESF phase, the site is found unsuitable, the studies will be stopped and the site restored to its natural state

  19. Hydrology of modern and late Holocene lakes, Death Valley, California

    Energy Technology Data Exchange (ETDEWEB)

    Grasso, D.N.

    1996-07-01

    Above-normal precipitation and surface-water runoff, which have been generally related to the cyclic recurrence of the El Nino-Southern Oscillation, have produced modern ephemeral lakes in the closed-basin Death Valley watershed. This study evaluates the regional hydroclimatic relations between precipitation, runoff, and lake transgressions in the Death Valley watershed. Recorded precipitation, runoff, and spring discharge data for the region are used in conjunction with a closed-basin, lake-water-budget equation to assess the relative contributions of water from these sources to modern lakes in Death Valley and to identify the requisite hydroclimatic changes for a late Holocene perennial lake in the valley. As part of the Yucca Mountain Site Characterization Program, an evaluation of the Quaternary regional paleoflood hydrology of the potential nuclear-waste repository site at Yucca Mountain, Nevada, was planned. The objectives of the evaluation were (1) to identify the locations and investigate the hydraulic characteristics of paleofloods and compare these with the locations and characteristics of modern floods, and (2) to evaluate the character and severity of past floods and debris flows to ascertain the potential future hazards to the potential repository during the pre-closure period (US Department of Energy, 1988). This study addresses the first of these objectives, and the second in part, by assessing and comparing the sizes, locations, and recurrence rates of modern, recorded (1962--83) floods and late Holocene paleofloods for the 8,533-mi{sup 2}, closed-basin, Death Valley watershed with its contributing drainage basins in the Yucca Mountain site area.

  20. Hydrology of modern and late Holocene lakes, Death Valley, California

    International Nuclear Information System (INIS)

    Grasso, D.N.

    1996-01-01

    Above-normal precipitation and surface-water runoff, which have been generally related to the cyclic recurrence of the El Nino-Southern Oscillation, have produced modern ephemeral lakes in the closed-basin Death Valley watershed. This study evaluates the regional hydroclimatic relations between precipitation, runoff, and lake transgressions in the Death Valley watershed. Recorded precipitation, runoff, and spring discharge data for the region are used in conjunction with a closed-basin, lake-water-budget equation to assess the relative contributions of water from these sources to modern lakes in Death Valley and to identify the requisite hydroclimatic changes for a late Holocene perennial lake in the valley. As part of the Yucca Mountain Site Characterization Program, an evaluation of the Quaternary regional paleoflood hydrology of the potential nuclear-waste repository site at Yucca Mountain, Nevada, was planned. The objectives of the evaluation were (1) to identify the locations and investigate the hydraulic characteristics of paleofloods and compare these with the locations and characteristics of modern floods, and (2) to evaluate the character and severity of past floods and debris flows to ascertain the potential future hazards to the potential repository during the pre-closure period (US Department of Energy, 1988). This study addresses the first of these objectives, and the second in part, by assessing and comparing the sizes, locations, and recurrence rates of modern, recorded (1962--83) floods and late Holocene paleofloods for the 8,533-mi 2 , closed-basin, Death Valley watershed with its contributing drainage basins in the Yucca Mountain site area

  1. ACUTE MOUNTAIN SICKNESS

    Directory of Open Access Journals (Sweden)

    Jakub Krzeszowiak

    2012-03-01

    Full Text Available This paper presents the most likely pathophysiological causes of the development of acute mountain sickness (AMS, also known as altitude sickness, its pulmonary form i.e. high altitude pulmonary edema (HAPE, and high altitude cerebral edema (HACE. These diseases constitute extraordinary environmental hazards because they are directly connected with low atmospheric pressure, and thus low partial oxygen pressure. The above adverse atmospheric conditions start to affect humans already at an altitude of 2,500 meters above the sea level and, coupled with extreme physical exertion, can quickly lead to respiratory alkalosis, which is not present under any other conditions in the lowlands. Mountaineering above 4,500 m a.s.l. leads to hypoxia of internal organs and, primarily, reduced renal perfusion with all its consequences. The above adverse changes, combined with inadequate acclimatization, can lead to a situation of imminent danger to life and health. This paper describes in detail the consequences of acute mountain sickness, which can ultimately lead to the development of AMS and one of severe forms of HACE and/or HAPE.

  2. Hydrological processes in small catchments of mountain headwater lakes: The Tatra Mountains

    Czech Academy of Sciences Publication Activity Database

    Křeček, J.; Turek, Jan; Ljungren, E.; Stuchlík, E.; Šporka, F.

    2006-01-01

    Roč. 61, Suppl. 18 (2006), S1-S10 ISSN 0006-3088 R&D Projects: GA ČR GA103/04/0214 Grant - others:MSM(CZ) 6840770002; EC(XE) GOCE-CT-2003-505540; EC(XE) EVK1-CT-1999-00032 Institutional research plan: CEZ:AV0Z60170517 Keywords : alpine catchments * evapotranspiration * runoff genesis * precipitation Subject RIV: DA - Hydrology ; Limnology Impact factor: 0.213, year: 2006

  3. Lead Levels in the Bones of Small Rodents from Alpine and Subalpine Habitats in the Tian-Shan Mountains, Kyrgyzstan

    Directory of Open Access Journals (Sweden)

    Zuzana Ballová

    2018-01-01

    Full Text Available High mountain areas are an appropriate indicator of anthropogenic lead (Pb, which can reach remote mountain ranges through long distance atmospheric transport. We compared the content of Pb in ecologically equivalent rodent species from Tian-Shan with European mountain ranges including the Tatra, Vitosha and Rila mountains. We used bone tissues from terminal tail vertebrae of small rodents for detection of Pb levels through electro-thermal atomic absorption spectroscopy (AAS. The tailbones of Tian-Shan rodents had significantly lower Pb levels than snow voles from the Tatra Mountains, but there was no significant difference in comparison with the Vitosha and Rila mountains. We can conclude that Tian-Shan shows lower pollution by Pb than the Tatras, which may be a result of prolonged industrialization of north-western Europe and strongly prevailing west winds in this region.

  4. Temporal Behavior of Lake Size-Distribution in a Thawing Permafrost Landscape in Northwestern Siberia

    Directory of Open Access Journals (Sweden)

    Johanna Mård Karlsson

    2014-01-01

    Full Text Available Arctic warming alters regional hydrological systems, as permafrost thaw increases active layer thickness and in turn alters the pathways of water flow through the landscape. Further, permafrost thaw may change the connectivity between deeper and shallower groundwater and surface water altering the terrestrial water balance and distribution. Thermokarst lakes and wetlands in the Arctic offer a window into such changes as these landscape elements depend on permafrost and are some of the most dynamic and widespread features in Arctic lowland regions. In this study we used Landsat remotely sensed imagery to investigate potential shifts in thermokarst lake size-distributions, which may be brought about by permafrost thaw, over three distinct time periods (1973, 1987–1988, and 2007–2009 in three hydrological basins in northwestern Siberia. Results revealed fluctuations in total area and number of lakes over time, with both appearing and disappearing lakes alongside stable lakes. On the whole basin scales, there is no indication of any sustained long-term change in thermokarst lake area or lake size abundance over time. This statistical temporal consistency indicates that spatially variable change effects on local permafrost conditions have driven the individual lake changes that have indeed occurred over time. The results highlight the importance of using multi-temporal remote sensing data that can reveal complex spatiotemporal variations distinguishing fluctuations from sustained change trends, for accurate interpretation of thermokarst lake changes and their possible drivers in periods of climate and permafrost change.

  5. Isotope method to study the replenishment the lakes and downstream groundwater in Badain Jaran desert

    International Nuclear Information System (INIS)

    Chen Jiansheng; Fan Zhechao; Gu Weizu; Zhao Xia; Wang Jiyang

    2003-01-01

    In the paper, the sources of spring water and well water of Qilian Mountain's north side, Longshou Mountain, Badain Jaran Desert, Gurinai, Guaizi Lake, and Ejina Basin are studied by the methods of environmental isotopes and water chemistry. The groundwater of downstream areas (such as Badain Jaran Desert) is found that it is recharged by the precipitation of Qilian Mountain, and the average recharge elevation is 3300 m. Lots of naked limestones layers exist at the mountaintop of Qilian Mountain. The snow water of Qilian Mountain melts and directly infiltrates into deep layer passing through karst stratum or Big Fault in Front of the Mountain, and directly recharges into Badain Jaran Desert and its downstream areas passing through Longshou Mountain. The calcareous cementation and travertine, found in the lakes of the desert, approve that the groundwater passed the limestone layer. Confined water recharges shallow aquifer by means of leakage. The groundwater recharge volume is six hundreds millions cubic meters per year by calculating the evaporation amount, and the age of confined groundwater is 20-30 years. (authors)

  6. The influence of climate change to European Lakes, with a special emphasis in the Balkan Region

    International Nuclear Information System (INIS)

    Kuusisto, Esko

    2004-01-01

    There are almost one and half million lakes in Europe, if small water bodies with an area down to 0.001 km 2 are included. The total area of lakes is over 200.000 km 2 , in addition the man-made reservoirs cover almost 100.000 km 2 . The largest lakes are located in the zone extending from southwestern Sweden through Finland to Russia, but there are many important lakes also in central and southern Europe. The Balkan countries have altogether about ten thousand lakes with a total area of over 4000 km 2 and total volume of almost loo km 3 . Over half of the total volume is in Lake Ohrid, which ranks the seventh in Europe both as to the volume and as to the maximum depth. However, there are around thirty lakes in Europe with their surface area larger than that of Lake Ohrid. In addition to the lakes, the Balkan countries also have thousands of reservoirs with a total water storage capacity of over 50 km 3 . The response of European lakes to climate change can be discussed by dividing the lakes into five categories: 1) deep temperate lakes, 2) shallow temperate lakes, 3) mountain lakes, 4) boreal lakes and 5) arctic lakes. The lakes in the Balkan region fall belong into the first three categories. Most of the deep temperate lakes are warm monomictic; convective overturn occurs in winter or early spring. The future climate change may suppress this overturn, giving these lakes the classification of oligomictic. This implies the enhancement of anoxic bottom conditions and an increased risk of eutrophication. The oxygen conditions can also be expected to deteriorate due to increased bacterial activity in deep waters and superficial bottom sediment. In shallow temperate lakes, higher water temperatures in the future will induce intensified primary production and bacterial decomposition. The probability of harmful extreme events, e.g. the mass production of algae, will increase. The impacts may extend to fishing and recreational use. In lakes with relatively long water

  7. Contrasting evolution patterns between glacier-fed and non-glacier-fed lakes in the central Tibetan Plateau and driving force analysis

    Science.gov (United States)

    Song, C.; Sheng, Y.

    2015-12-01

    High-altitude lakes in the Tibetan Plateau (TP) showed strong spatio-temporal variability during past decades. The lake dynamics can be associated with several key factors including lake type, supply of glacial meltwater, local climate variations. It is important to differentiate these factors when analyzing the driving force of lakes dynamics. With a focus on lakes over the Tanggula Mountains of the central TP, this study investigates the temporal evolution patterns of lake area and water level of different types: glacier-fed closed lake, non-glacier-fed closed lake and upstream lake (draining into closed lakes). We collected all available Landsat archive data and quantified the inter-annual variability of lake extents. Results show accelerated expansions of both glacier-fed and non-glacier-fed lakes during 1970s-2013, and different temporal patterns of the two types of lakes: the non-glacier-fed lakes displayed a batch-wise growth pattern, with obvious growth in 2002, 2005 and 2011 and slight changes in other years, while glacier-fed lakes showed steady expanding tendency. The contrasting patterns are confirmed by the distinction of lake level change between the two groups derived from satellite altimetry during 2003-2009. The upstream lakes remained largely stable due to natural drainage regulation. The intermittent expansions for non-glacier-fed lakes were found to be related to excessive precipitation events and positive "precipitation-evaporation". In contrast, glacier-fed lake changes showed weak correlations with precipitation variations, which imply a joint contribution from glacial meltwater to water budgets. A simple estimation reveals that the increased water storage for all of examined lakes contributed from precipitation/evaporation (0.31±0.09 Gt/yr) slightly overweighed the glacial meltwater supply (0.26±0.08 Gt/yr).

  8. Pollution at Lake Mariut

    International Nuclear Information System (INIS)

    Nour ElDin, H.; Halim, S. N.; Shalby, E.

    2004-01-01

    Lake Mariut, south Alexandria, Egypt suffered in the recent decades from intensive pollution as a result of a continuous discharge of huge amounts of agriculture wastewater that contains a large concentration of the washed pesticides and fertilizers in addition to domestic and industrial untreated wastewater. The over flow from the lake is discharged directly to the sea through El-Max pumping station via EI-Umum drain. Lake Mariout is surrounded by a huge number of different industrial activities and also the desert road is cutting the lake, this means that a huge number of various pollutants cycle through the air and settle down in the lake, by the time and during different seasons these pollutants after accumulation and different chemical interactions will release again from the lake to the surrounding area affecting the surrounding zone

  9. Eutrophication monitoring for Lake Superior's Chequamegon ...

    Science.gov (United States)

    A priority for the Lake Superior CSMI was to identify susceptible nearshore eutrophication areas. We developed an integrated sampling design to collect baseline data for Lake Superior’s Chequamegon Bay to understand how nearshore physical processes and tributary loading relate to observed chlorophyll concentrations. Sampling included ship-based water samples combined with vertical CTD casts, continuous in situ towing and data collected from an autonomous underwater glider. Sampling was conducted during June, July and September. The glider collected regional data as part of three extended missions in Lake Superior over the same periods. During the study, two significant storm events impacted the western end of Lake Superior; the first occurred during July 11-12, with 8-10 inches of rain in 24hrs, and the second on July 21 with winds in excess of 161 km/h. Using GIS software, we organized these diverse temporal data sets along a continuous time line with temporally coincident Modis Satellite data to visualize surface sediment plumes in relation to water quality measurements. Preliminary results suggest that both events impacted regional water quality, and that nearshore physical forces (upwelling and currents) influenced the spatial variability. Results comparing in situ measures with remotely sensed images will be discussed. not applicable

  10. Great Lakes Literacy Principles

    Science.gov (United States)

    Fortner, Rosanne W.; Manzo, Lyndsey

    2011-03-01

    Lakes Superior, Huron, Michigan, Ontario, and Erie together form North America's Great Lakes, a region that contains 20% of the world's fresh surface water and is home to roughly one quarter of the U.S. population (Figure 1). Supporting a $4 billion sport fishing industry, plus $16 billion annually in boating, 1.5 million U.S. jobs, and $62 billion in annual wages directly, the Great Lakes form the backbone of a regional economy that is vital to the United States as a whole (see http://www.miseagrant.umich.edu/downloads/economy/11-708-Great-Lakes-Jobs.pdf). Yet the grandeur and importance of this freshwater resource are little understood, not only by people in the rest of the country but also by many in the region itself. To help address this lack of knowledge, the Centers for Ocean Sciences Education Excellence (COSEE) Great Lakes, supported by the U.S. National Science Foundation and the National Oceanic and Atmospheric Administration, developed literacy principles for the Great Lakes to serve as a guide for education of students and the public. These “Great Lakes Literacy Principles” represent an understanding of the Great Lakes' influences on society and society's influences on the Great Lakes.

  11. The Key Lake project

    International Nuclear Information System (INIS)

    1991-01-01

    Key Lake is located in the Athabasca sand stone basin, 640 kilometers north of Saskatoon, Saskatchewan, Canada. The three sources of ore at Key Lake contain 70 100 tonnes of uranium. Features of the Key Lake Project were described under the key headings: work force, mining, mill process, tailings storage, permanent camp, environmental features, worker health and safety, and economic benefits. Appendices covering the historical background, construction projects, comparisons of western world mines, mining statistics, Northern Saskatchewan surface lease, and Key Lake development and regulatory agencies were included

  12. Mountainous areas and decentralized energy planning: Insights from Greece

    International Nuclear Information System (INIS)

    Katsoulakos, Nikolas M.; Kaliampakos, Dimitris C.

    2016-01-01

    Mountainous areas have particular characteristics, whose influence on energy planning is explored in this paper, through a suitably tailored methodology applied to the case of Greece. The core element of the methodology is a linear optimization model with a “total cost” objective function, which includes financial, as well as external costs and benefits. Altitude proves to have decisive influence on energy optimization results, because it affects energy demand. The improvement of local energy systems provides greater socioeconomic benefits in mountainous settlements, due to the high shares of renewables and energy efficiency interventions in the optimal solutions. Energy poverty can be alleviated by redesigning local energy systems and the structure of the energy market. However, spatial and aesthetic restrictions, presented often in mountainous settlements, may affect the operational costs of energy systems, which is a crucial parameter for confronting energy poverty. Furthermore, the study indicates that it could be better to electrify remote areas, far from electricity grids, by decentralized systems than by grid expansion. The results of this study and the assumptions made about the way in which energy market should function, could be utilized for reconsidering energy policy measures, aiming at supporting sensitive societies to improve their development perspectives. - Highlights: •The influence of mountains' characteristics on energy planning was analyzed. •Optimal energy solutions present differentiations with respect to altitude. •Greater socioeconomic benefits by energy optimization in mountainous areas. •Remoteness favors the development of decentralized energy systems. •The study is based on data from Greece.

  13. Ecological impact of transhumance on the trophic state of alpine lakes in Gran Paradiso National Park

    Directory of Open Access Journals (Sweden)

    Tiberti R.

    2014-01-01

    Full Text Available Transhumance – the summer transfer of livestock to highland pastures – is a traditional practice in the European Alps and is considered an integral part of the mountain ecosystem. Mountain lakes are generally oligotrophic systems and are particularly sensitive to the nutrient input caused by livestock. The aim of the present study was to quantify the impact of livestock grazing on the trophic state of high-altitude lakes in an area where transhumance is a traditional practice (Gran Paradiso National Park, Western Italian Alps, taking into account its dual value of ecosystem component and potential threat to lakes’ trophic status. The impact of flocks and herds grazing was estimated on sensitive parameters related to the trophic state of alpine lakes: water transparency, nutrient content, bacterial load and chlorophyll-a concentration. Transhumance produced a significant increase in the trophic state of lakes with high grazing pressure, but little or no effect was found at soft-impacted lakes. Even though heavy-impacted lakes represent a minority of the studied lakes (three out of twenty, we indicated conservation measures such as fencing, wastewater treatment and livestock exclosure to be tested in Gran Paradiso National Park.

  14. Development of Petrov glacial-lake system (Tien Shan and outburst risk assessment

    Directory of Open Access Journals (Sweden)

    I. A. Torgoev

    2013-01-01

    Full Text Available Global climate warming causes an intensive melting and retreat of glaciers in the Tien Shan mountains. Melting water of glaciers causes overfilling of high mountain lakes. The increase of the surface and volume of the Petrov Lake accompanied with the decrease of stability of the dam represents an extremely dangerous situation that can produce a natural disaster. Failure can happen due to erosion, a buildup of water pressure, an earthquake or if a large enough portion of a glacier breaks off and massively displaces the waters in a glacial lake at its base. In case of the lake dam rupture, flooding of a disposal site of highly toxic tailing from the gold mine Kumtor is a threat. If this happens, the toxic waste containing cyanides would contaminate a large area in the Naryn (Syrdarya river basin. Even if the flooding of the disposal site does not occur, the damage after lake dam fracture will be immense due to the glacial lake outburst flood may be a devastating mudslide. In order to prevent or reduce the risk of this event we recommend performing engineering surveys for the development and implementation of the project for the controlled reduction of water level in the Blue Bay of the Petrov Lake to a safe volume.

  15. Detailed modeling of mountain wave PSCs

    Directory of Open Access Journals (Sweden)

    S. Fueglistaler

    2003-01-01

    Full Text Available Polar stratospheric clouds (PSCs play a key role in polar ozone depletion. In the Arctic, PSCs can occur on the mesoscale due to orographically induced gravity waves. Here we present a detailed study of a mountain wave PSC event on 25-27 January 2000 over Scandinavia. The mountain wave PSCs were intensively observed by in-situ and remote-sensing techniques during the second phase of the SOLVE/THESEO-2000 Arctic campaign. We use these excellent data of PSC observations on 3 successive days to analyze the PSCs and to perform a detailed comparison with modeled clouds. We simulated the 3-dimensional PSC structure on all 3 days with a mesoscale numerical weather prediction (NWP model and a microphysical box model (using best available nucleation rates for ice and nitric acid trihydrate particles. We show that the combined mesoscale/microphysical model is capable of reproducing the PSC measurements within the uncertainty of data interpretation with respect to spatial dimensions, temporal development and microphysical properties, without manipulating temperatures or using other tuning parameters. In contrast, microphysical modeling based upon coarser scale global NWP data, e.g. current ECMWF analysis data, cannot reproduce observations, in particular the occurrence of ice and nitric acid trihydrate clouds. Combined mesoscale/microphysical modeling may be used for detailed a posteriori PSC analysis and for future Arctic campaign flight and mission planning. The fact that remote sensing alone cannot further constrain model results due to uncertainities in the interpretation of measurements, underlines the need for synchronous in-situ PSC observations in campaigns.

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

    Science.gov (United States)

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

    2009-01-01

    Bear Lake, on the Idaho-Utah border, lies in a fault-bounded valley through which the Bear River flows en route to the Great Salt Lake. Surficial deposits in the Bear Lake drainage basin provide a geologic context for interpretation of cores from Bear Lake deposits. In addition to groundwater discharge, Bear Lake received water and sediment from its own small drainage basin and sometimes from the Bear River and its glaciated headwaters. The lake basin interacts with the river in complex ways that are modulated by climatically induced lake-level changes, by the distribution of active Quaternary faults, and by the migration of the river across its fluvial fan north of the present lake. The upper Bear River flows northward for ???150 km from its headwaters in the northwestern Uinta Mountains, generally following the strike of regional Laramide and late Cenozoic structures. These structures likely also control the flow paths of groundwater that feeds Bear Lake, and groundwater-fed streams are the largest source of water when the lake is isolated from the Bear River. The present configuration of the Bear River with respect to Bear Lake Valley may not have been established until the late Pliocene. The absence of Uinta Range-derived quartzites in fluvial gravel on the crest of the Bear Lake Plateau east of Bear Lake suggests that the present headwaters were not part of the drainage basin in the late Tertiary. Newly mapped glacial deposits in the Bea