Sample records for remote mountain lake

  1. Lead Speciation in remote Mountain Lakes

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


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

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

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


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

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

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


    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.

  4. 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

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


    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.

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

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


    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

    Wathne, Bente M. [ed.


    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

    Andrea LAMI


    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.

  8. Food Web Topology in High Mountain Lakes.

    Javier Sánchez-Hernández

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

  9. Remote and Roadside Lake Study : 1983

    US Fish and Wildlife Service, Department of the Interior — Personnel of the U.S. Fish and Wildlife Service, Kenai Fishery Resources Station, conducted fishery surveys on 18 remote and roadside lakes of the Kenai National...

  10. Mapping Glacial Lake Changes in Mountain Areas of Central Asia with Landsat Imagery during 1990-2010

    LI, Junli; Chen, Xi; Bao, Anming


    Central Asia is one of the world most vulnerable areas responding to global change. Glacier lakes in alpine regions remain sensitive to climatic change and fluctuate with temperature and precipitation variations. Study shows that glaciers in Central Asia have retreated dramatically, leading to the expansion of the existing glacial lakes and the emergence of many new glacial lakes. The existence of these lakes increases the possibility of outburst flood during the ice melting season, which can bring a disaster to the downstream area. Mapping glacial lakes and monitoring their changes would improve our understanding of regional climate change and glacier related hazards. Glacial lakes in Central Asia are mainly located at the Tianshan Mountains, the Altai Mountains and Kunlun Mountains with average elevation more than 1500 meters. Most of these lakes are supplied with the glaciers and snowmelt water during the summer seasons. Satellite remote sensing provides an efficient and objective tool to analyse the status and variations of glacial lakes. The increased availability of remote sensing sensors with appropriate spatial and temporal resolutions, broad coverage makes lake investigations more feasible and cost-effective. The paper intends to map glacier lake changes in the Tianshan Mountains, the Altai Mountains and Kunlun Mountains with Landsat imagery. About 400 scenes of Landsat images in circa 1990, circa 2000 and 2010 are used to map the glacial lakes over the Central Asia, and the temporal processes and spatial patterns of these lake changes are also analysed, so as to find the relations between lake changes and region climate change. Over 12 000 glacial lakes were mapped in circa 2010, and the most of them are located the Altai Mountains and the Tianshan Mountains. The result shows that the numbers and areas of the glacial lakes in the Altai Mountain remain stable. The Tianshan Mountain have experienced changes in the last two decades, and about a half number

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

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


    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.

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

    Emmer, Adam; Merkl, Sarah; Mergili, Martin


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

  13. Hanford Reach - Strategic Control of Phragmites Within Saddle Mountain Lakes

    US Fish and Wildlife Service, Department of the Interior — The Saddle Lakes Fire of 2015 burned 14,200 acres of habitat on Saddle Mountain National Wildlife Refuge, part of the Hanford Reach National Monument. Within the...

  14. Thermal regimes of Rocky Mountain lakes warm with climate change

    Roberts, James J.; Fausch, Kurt D.; Schmidt, Travis S.; Walters, David M.


    Anthropogenic climate change is causing a wide range of stresses in aquatic ecosystems, primarily through warming thermal conditions. Lakes, in response to these changes, are experiencing increases in both summer temperatures and ice-free days. We used continuous records of lake surface temperature and air temperature to create statistical models of daily mean lake surface temperature to assess thermal changes in mountain lakes. These models were combined with downscaled climate projections to predict future thermal conditions for 27 high-elevation lakes in the southern Rocky Mountains. The models predict a 0.25°C·decade-1increase in mean annual lake surface temperature through the 2080s, which is greater than warming rates of streams in this region. Most striking is that on average, ice-free days are predicted to increase by 5.9 days ·decade-1, and summer mean lake surface temperature is predicted to increase by 0.47°C·decade-1. Both could profoundly alter the length of the growing season and potentially change the structure and function of mountain lake ecosystems. These results highlight the changes expected of mountain lakes and stress the importance of incorporating climate-related adaptive strategies in the development of resource management plans.

  15. Vertical gradients of PCBs and PBDEs in fish from European high mountain lakes

    Grimalt, J. O.; Gallego, E.; Bartrons, M.; Catalan, J.; Camarero, L.; Stuchlik, E.; Battarbee, R.


    A first case of temperature-dependent distribution of polybromodiphenyl eters (PBDEs) in remote areas is shown. Analysis of these compounds in fish from Pyrenean lakes distributed along an altitudinal transect shows higher concentrations at lower temperatures, as predicted in the global distillation model. Conversely, no temperature-dependent distribution is observed in a similar transect in the Tatra mountains (Central Europe) nor in fish from high mountain lakes distributed throughout Europe. The fish concentrations of polychlorobiphenyls (PCBs) examined for comparison showed significant temperature correlations in all these studied lakes. In the interval of feasible temperatures for high mountain lakes, cold trapping of both PCBs and PBDEs concerned the less volatile congeners. In the Pyrenean lake transect the concentrations of PCBs and PBDEs in fish were correlated despite the distinct use of these compounds and their 40 year time-lag of emissions to the environment. Thus, temperature effects have overcome these anthropogenic differences constituting at present the main process determining their distributions. The cases of distinct PBDE and PCB behavior in high mountains can therefore be interpreted to reflect early stages in the environmental distribution of the former compounds.

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

    Michela ROGORA


    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.

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

    Jirí NEDOMA


    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.

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

    Jordi Catalan


    , 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.

  19. A database of georeferenced nutrient chemistry data for mountain lakes of the Western United States

    Williams, Jason; Labou, Stephanie G.


    Human activities have increased atmospheric nitrogen and phosphorus deposition rates relative to pre-industrial background. In the Western U.S., anthropogenic nutrient deposition has increased nutrient concentrations and stimulated algal growth in at least some remote mountain lakes. The Georeferenced Lake Nutrient Chemistry (GLNC) Database was constructed to create a spatially-extensive lake chemistry database needed to assess atmospheric nutrient deposition effects on Western U.S. mountain lakes. The database includes nitrogen and phosphorus water chemistry data spanning 1964-2015, with 148,336 chemistry results from 51,048 samples collected across 3,602 lakes in the Western U.S. Data were obtained from public databases, government agencies, scientific literature, and researchers, and were formatted into a consistent table structure. All data are georeferenced to a modified version of the National Hydrography Dataset Plus version 2. The database is transparent and reproducible; R code and input files used to format data are provided in an appendix. The database will likely be useful to those assessing spatial patterns of lake nutrient chemistry associated with atmospheric deposition or other environmental stressors.

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

    Jiao Liping [Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China); Key Laboratory of Global Change and Marine-Atmospheric Chemistry, State Oceanic Administration, 178 Daxue Road, Xiamen, Fijian (China); Third Institute of Oceanography, State Oceanic Administration, 178 Daxue Road, Xiamen, Fujian (China); Zheng, Gene J. [Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China); Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong (China); Minh, Tu Binh; Richardson, Bruce [Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China); Chen Liqi; Zhang Yuanhui [Key Laboratory of Global Change and Marine-Atmospheric Chemistry, State Oceanic Administration, 178 Daxue Road, Xiamen, Fijian (China); Third Institute of Oceanography, State Oceanic Administration, 178 Daxue Road, Xiamen, Fujian (China); Yeung, Leo W.; Lam, James C.W. [Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China); Yan, Xulin [Key Laboratory of Global Change and Marine-Atmospheric Chemistry, State Oceanic Administration, 178 Daxue Road, Xiamen, Fijian (China); Third Institute of Oceanography, State Oceanic Administration, 178 Daxue Road, Xiamen, Fujian (China); Lam, Paul K.S. [Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China)], E-mail:; Wong, Ming H. [Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong (China)], E-mail:


    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.

  1. Radiometric dating of sediment records in European mountain lakes

    Peter G. APPLEBY


    Full Text Available Sediment cores from seven European mountain lakes collected as part of a study of palaeolimnogical records of climate change (the MOLAR project were dated radiometrically by 210Pb. In spite of the remote locations, only one site recorded more or less uniform sediment accumulation throughout the past 150 years. At three further sites the 210Pb record indicated uniform sedimentation up until ca 1950 but significant increases since then. Stratigraphic dates based on records of fallout 137Cs and 241Am showed that 210Pb supply rates to these core sites had nonetheless remained relatively constant and that the sediments could be dated by the CRS model. At the remaining sites there were indications of episodic changes in both sedimentation rates and 210Pb supply rates. Since the changes were not in proportion, neither of the simple dating models (CRS or CIC was applicable. Using the 137Cs and 241Am stratigraphic dates as reference points it was however possible to construct a realistic chronology for these cores by applying the CRS model piecewise to each time-bounded section.

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

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


    Semi-volatile organochlorine compounds (OC) were analyzed in remote Andean soils and lake sediments. The sampling sites covered a wide latitudinal gradient from 18 degrees S to 46 degrees 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, alpha- and gamma-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.

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

    Borghini, Francesca [Department of Environmental Sciences, University of Siena, Via Mattioli 4, 53100 Siena (Italy); Grimalt, Joan O. [Department of Environmental Chemistry (ICER-CSIC), Jordi Girona 18, 08034 Barcelona, Catalonia (Spain)]. E-mail:; Sanchez-Hernandez, Juan C. [Laboratory of Ecotoxicology, University of Castilla-La Mancha, Avda. Carlos III, s/n, 45071 Toledo (Spain); Barra, Ricardo [Aquatic Systems Research Unit, EULA - Chile Environmental Sciences Centre, University of Concepcion, Casilla 160-C, Concepcion (Chile); Garcia, Carlos J. Torres [Izan-a Atmospheric Observatory, National Institute of Meteorology, La Marina 20, 38071 Santa Cruz de Tenerife, Canary Islands (Spain); Focardi, Silvano [Department of Environmental Sciences, University of Siena, Via Mattioli 4, 53100 Siena (Italy)


    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, {alpha}- and {gamma}-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.

  4. Quantitative interpretation of Great Lakes remote sensing data

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


    The paper discusses the quantitative interpretation of Great Lakes remote sensing water quality data. Remote sensing using color information must take into account (1) the existence of many different organic and inorganic species throughout the Great Lakes, (2) the occurrence of a mixture of species in most locations, and (3) spatial variations in types and concentration 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 show the advantage of using a radiative transfer model. Spectral absorptance and backscattering coefficients for two inorganic sediments are reported.

  5. Remote assessment of reserve capacity of outburst alpine lakes

    V. G. Konovalov


    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.

  6. Interim report on pesticide levels in fish from two industrial lakes at Rocky Mountain Arsenal

    US Fish and Wildlife Service, Department of the Interior — Report on pesticide levels from fish taken from Lower Derby Lake and Lake Ladora at the Rocky Mountain Arsenal in 1975. Dieldrin and aldrin levels were measured in...

  7. Modelling reversibility of central European mountain lakes from acidification: Part II – the Tatra Mountains

    J. Kopácek


    Full Text Available A dynamic, process-based model of surface water acidification, MAGIC7, has been applied to four representative alpine lakes in the Tatra Mountains (Slovakia and Poland. The model was calibrated for a set of 12 to 22-year experimental records of lake water composition. Surface water and soil chemistry were reconstructed from 1860 to 2002 and forecast to 2050 based on the reduction in sulphur and nitrogen emissions presupposed by the Gothenburg Protocol. Relatively small changes in the soil C:N ratios were not sufficient to simulate observed changes in NO3‾ concentrations, so an alternative empirical approach of changes in terrestrial N uptake was applied. Measured sulphate sorption isotherms did not allow calibration of the pattern of sulphate response in the lakes, indicating that other mechanisms of S release were also important. The lake water chemistry exhibited significant changes during both the acidification advance (1860 to 1980s and retreat (1980s to 2010. An increase in lake water concentrations of strong acid anions (SAA; 104–149 μeq l–1 was balanced by a decline in HCO3‾ (13–62 μeq l–1 and an increase in base cations (BC; 42–72 μeq l–1, H+ (0-18 μeq l–1, and Alin+ (0–26 μeq l–1. The carbonate buffering system was depleted in three lakes. In contrast, lake water concentrations of SAA, BC, H+, and Alin+ decreased by 57–82, 28–42, 0–11, and 0–22 μeq l–1, respectively, the carbonate buffering system was re-established, and HCO3‾ increased by 1–21 μeq l–1 during the chemical reversal from atmospheric acidification (by 2000. The MAGIC7 model forecasts a slight continuation in this reversal for the next decade and new steady-state conditions thereafter. Gran alkalinity should come back to 1950s levels (0–71 μeq l–1 in all lakes after 2010. Partial recovery of the soil pool of exchangeable base cations can be expected in one catchment, while only conservation of the current conditions is

  8. Spatio-temporal development of high-mountain lakes in the headwaters of the Amu Darya River (Central Asia)

    Mergili, Martin; Müller, Johannes P.; Schneider, Jean F.


    The sources of the Amu Darya, one of the major Central Asian rivers draining to the Aral Sea, are located in the glacierized high-mountain areas of Tajikistan, Kyrgyzstan and Afghanistan. There, climate change and the resulting retreat of glaciers have led to the formation of numerous new glacial lakes. Other lakes in the area are embedded in older glacial landscapes (erosion lakes) or retained by block or debris dams (e.g., Lake Sarez). A multi-temporal lake inventory is prepared and analysed, based on remotely sensed data. Corona images from 1968 are used as well as more up-to-date ASTER and Landsat 7 scenes. 1642 lakes are mapped in total, 652 out of them are glacial lakes. 73% of all lakes are located above 4000 m a.s.l. Glacial lakes, abundant in those areas where glacier tongues retreat over flat or moderately steep terrain, have experienced a significant growth, even though changes are often superimposed by short-term fluctuations. The analysis results also indicate a shifting of the growth of glacial lakes from the south western Pamir to the central and northern Pamir during the observation period. This trend is most likely associated with more elevated contribution areas in the central and northern Pamir. The lakes of the other types have remained constant in size in general. The lake development reflects changes in the state of the water resources in the study area on the one hand and determines the level of lake outburst hazards on the other hand.

  9. 77 FR 75186 - Notice of Closure, Target Shooting Public Safety Closure on the Lake Mountains in Utah County, UT


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

  10. Climate change and Saharan dust drive recent cladoceran and primary production changes in remote alpine lakes of Sierra Nevada, Spain.

    Jiménez, Laura; Rühland, Kathleen M; Jeziorski, Adam; Smol, John P; Pérez-Martínez, Carmen


    Recent anthropogenic climate change and the exponential increase over the past few decades of Saharan dust deposition, containing ecologically important inputs of phosphorus (P) and calcium (Ca), are potentially affecting remote aquatic ecosystems. In this study, we examine changes in cladoceran assemblage composition and chlorophyll-a concentrations over the past ~150 years from high-resolution, well-dated sediment cores retrieved from six remote high mountain lakes in the Sierra Nevada Mountains of Southern Spain, a region affected by Saharan dust deposition. In each lake, marked shifts in cladoceran assemblages and chlorophyll-a concentrations in recent decades indicate a regional-scale response to climate and Saharan dust deposition. Chlorophyll-a concentrations have increased since the 1970s, consistent with a response to rising air temperatures and the intensification of atmospheric deposition of Saharan P. Similar shifts in cladoceran taxa across lakes began over a century ago, but have intensified over the past ~50 years, concurrent with trends in regional air temperature, precipitation, and increased Saharan dust deposition. An abrupt increase in the relative abundance of the benthic cladoceran Alona quadrangularis at the expense of Chydorus sphaericus, and a significant increase in Daphnia pulex gr. was a common trend in these softwater lakes. Differences in the magnitude and timing of these changes are likely due to catchment and lake-specific differences. In contrast with other alpine lakes that are often affected by acid deposition, atmospheric Ca deposition appears to be a significant explanatory factor, amongst others, for the changes in the lake biota of Sierra Nevada that has not been previously considered. The effects observed in Sierra Nevada are likely occurring in other Mediterranean lake districts, especially in soft water, oligotrophic lakes. The predicted increases in global temperature and Saharan dust deposition in the future will further

  11. Temporal patterns of glacial lake evolution in high-mountain environments

    Mergili, Martin; Emmer, Adam; Viani, Cristina; Huggel, Christian


    Lakes forming at the front of retreating glaciers are characteristic features of high-mountain areas in a warming climate. Typically, lakes shift from the proglacial phase (lake is in direct contact with glacier) to a glacier-detached (no direct contact) and finally to a non-glacial phase (lake catchment is completely deglaciated) of lake evolution. Apart from changing glacier-lake interactions, each stage is characterized by particular features of lake growth, and by the lake's susceptibility to sudden drainage (lake outburst flood). While this concept appears to be valid globally, some mountain areas are rich in dynamically evolving proglacial lakes, while in others most lakes have already shifted to the glacier-detached or even non-glacial phase. In the present contribution we (i) explore and quantify the history of glacial lake formation and evolution over the past up to 70 years; (ii) assess the current situation of selected contrasting mountain areas (eastern and western European Alps, southern and northern Pamir, Cordillera Blanca); and (iii) link the patterns of lake evolution to the prevailing topographic and glaciological characteristics in order to improve the understanding of high-mountain geoenvironmental change. In the eastern Alps we identify only very few lakes in the proglacial stage. While many lakes appeared and dynamically evolved until the 1980s between 2550 m and 2800 m asl, most of them have lost glacier contact until the 2000s, whereas very few new proglacial lakes appeared at the same time. Even though a similar trend is observed in the higher western Alps, a more dynamic glacial lake evolution is observed there. The arid southern Pamir is characterized by a high number of proglacial lakes, mainly around 4500 m asl. There is strong evidence that glacial lake evolution is, after a highly dynamic phase between the 1970s and approx. 2000, decelerating. Few proglacial lakes exist in the higher and more humid, heavily glacierized northern Pamir

  12. Regional assessment of lake water clarity using satellite remote sensing

    David L. SKOLE


    Full Text Available Lake water clarity as measured by Secchi disk transparency (SDT is a cost-effective measure of water quality. However, in regions where there are thousands of lakes, sampling even a small proportion of those lakes for SDT year after year is cost prohibitive. Remote sensing has the potential to be a powerful tool for assessing lake clarity over large spatial scales. The overall objective of our study was to examine whether Landsat-7 ETM+ could be used to measure water clarity across a large range of lakes. Our specific objectives were to: 1 develop a regression model to estimate SDT from Landsat data calibrated using 93 lakes in Michigan, U.S.A., and to 2 examine how the distribution of SDT across the 93 calibration lakes influenced the model. Our calibration dataset included a large number of lakes with a wide range of SDT values that captured the summer statewide distribution of SDT values in Michigan. Our regression model had a much lower r2 value than previously published studies conducted on smaller datasets. To examine the importance of the distribution of calibration data, we simulated a calibration dataset with a different SDT distribution by sub-sampling the original dataset to match the distribution of previous studies. The sub-sampled dataset had a much higher percentage of lakes with shallow water clarity, and the resulting regression model had a much higher r2 value than our original model. Our study shows that the use of Landsat to measure water clarity is sensitive to the distribution of water clarity used in the calibration set.

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

    Guardamino, Lucía; Drenkhan, Fabian


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

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

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


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

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

    Arpit Aggarwal


    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

  16. Agriculture causes nitrate fertilization of remote alpine lakes

    Hundey, E. J.; Russell, S. D.; Longstaffe, F. J.; Moser, K. A.


    Humans have altered Earth's nitrogen cycle so dramatically that reactive nitrogen (Nr) has doubled. This has increased Nr in aquatic ecosystems, which can lead to reduced water quality and ecosystem health. Apportioning sources of Nr to specific ecosystems, however, continues to be challenging, despite this knowledge being critical for mitigation and protection of water resources. Here we use Δ17O, δ18O and δ15N from Uinta Mountain (Utah, USA) snow, inflow and lake nitrate in combination with a Bayesian-based stable isotope mixing model, to show that at least 70% of nitrates in aquatic systems are anthropogenic and arrive via the atmosphere. Moreover, agricultural activities, specifically nitrate- and ammonium-based fertilizer use, are contributing most (~60%) Nr, and data from other North American alpine lakes suggest this is a widespread phenomenon. Our findings offer a pathway towards more effective mitigation, but point to challenges in balancing food production with protection of important water resources.

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

    Lasker, A. Dwight


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

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

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


    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.

  19. Remote Sensing-Derived Bathymetry of Lake Poopó

    Adalbert Arsen


    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.


    T. Kutser


    Full Text Available Solving of several global and regional problems requires adequate data about lake water quality parameters like the amount and type of phytoplankton dominating in the lakes, the amount of dissolved and coloured dissolved organic matter and/or concentration of suspended sediment. Remote sensing is the only practical way to study many lakes provided it can produce sufficiently accurate estimates of the water characteristics. We studied optically very variable lakes in order to test both physics based methods and conventional band-ratio type algorithms in retrieval of water parameters. The modelled spectral library used in the physics based approach provided very good results for chlorophyll-a retrieval. The number of different concentrations of CDOM and suspended matter used in the simulations was too low to provide good estimates of these parameters. Extending the spectral library is currently in progress. Band-ratio type algorithms worked well in chlorophyll-a and CDOM retrieval. None of the algorithms tested for total suspended matter, organic suspended matter and inorganic suspended matter retrieval performed well enough and there is need in further testing.

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

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


    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

  2. Mountain Search and Rescue with Remotely Piloted Aircraft Systems

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


    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. Remote sensing study of Maumee River effects of Lake Erie

    Svehla, R.; Raquet, C.; Shook, D.; Salzman, J.; Coney, T.; Wachter, D.; Gedney, R.


    The effects of river inputs on boundary waters were studied in partial support of the task to assess the significance of river inputs into receiving waters, dispersion of pollutants, and water quality. The effects of the spring runoff of the Maumee River on Lake Erie were assessed by a combination of ship survey and remote sensing techniques. The imagery obtained from a multispectral scanner of the west basin of Lake Erie is discussed: this clearly showed the distribution of particulates throughout the covered area. This synoptic view, in addition to its qualitative value, is very useful in selecting sampling stations for shipboard in situ measurements, and for extrapolating these quantitative results throughout the area of interest.

  4. Hazard assessment of glacial lake outburst floods from Kyagar glacier, Karakoram mountains, China

    Haemmig, Christoph; Huss, Matthias; Keusen, Hansrudolf; Hess, Josef; Wegmüller, Urs; Ao, Zhigang; Kulubayi, Wubuli


    Kyagar glacier is located in the Chinese Karakoram mountains. The glacier tongue entirely blocks the riverbed in the upper Shaksgam valley and impounds a glacial lake, which was the source of several violent and disastrous glacial lake outburst floods (GLOFs). A GLOF early warning system was implemented between 2011 and 2013. We present an integrative analysis of the hazard potential of Kyagar lake, taking into account the ice flow dynamics of Kyagar glacier as well as the recent surface mass...

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

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


    Sediment quality guidelines and toxic equivalent factors have been used for assessment of the toxicity of sedimentary long-range atmospherically transported polycyclic aromatic hydrocarbons (PAHs) to the organisms living in high mountain European lakes. This method has provided indices that are consistent with experimental studies evaluating in situ sedimentary estrogenic activity or physiological response to AhR binding in fish from the same lakes. All examined lakes in north, central, west, northeast and southeast European mountains have shown sedimentary PAH concentrations that are above thresholds of no effect but only those situated in the southeast lakes district exhibited concentrations above the indices of probable effects. These mountains, Tatras, are also those having PAH concentrations of highest activity for AhR binding. Chrysene+triphenylene, dibenz[a]anthracene, benzo[k]fluoranthene and indeno[1,2,3-cd]pyrene are the main compounds responsible for the observed toxic effects. Copyright 2010 Elsevier Inc. All rights reserved.

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

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


    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.

  7. Eutrophication dynamics in lake Baikal from remote sensing data

    Pitarch, Jaime; Silow, Eugene; Krashchuk, Lyudmila S.; Pislegina, Elena V.; Shimaraeva, Svetlana V.; Izmestyeva, Lyubov R.; Santoleri, Rosalia; Moore, Marianne V.


    Lake Baikal, one of the oldest lakes on earth, the deepest (1642 m), and the largest in volume (23,615 cubic km) of all of Earth's freshwater bodies, is located nearly in the very center of Asia, 456 m above sea level. Baikal stretches for 636 km from the southwest to the northeast between 51°28' and 55°47' N, and 103°43' and 109°58' E. The area of Baikal's watershed is over 550,000 square km. Baikal is also unique in that its waters are rich in oxygen all the way to the bottom of the lake. A large number of the species living in Lake Baikal are endemic. In 1996, Lake Baikal was named a UNESCO Heritage Site, with Russia pledging to protect it. A number of recent studies have reported degradation of the benthic littoral zone such as proliferation of benthic algae, death of snails and endemic sponges, large coastal wash-ups of dead benthic algae and macrophytes, blooms of toxin-producing benthic cyanobacteria, and inputs of industrial contaminants. In the open, pelagic basins, changes in the eutrophication and water transparency have also been noticed. Such studies were based on in-situ collected data, at different spatial and temporal frequencies. Remote sensing (RS) offers a comprehensive monitoring of all littoral and open areas of the lake at a high and regular time frequency. The amount of ecological information retrieved by RS is much lower than that provided by in-situ data, but RS can determine the representativeness of the chosen in-situ stations and detect un-sampled zones that need monitoring. Additionally, RS provides a harmonized methodology in space and time, which is crucial if statistical information is going to be derived. On its turn, in-situ data is required as a ground truth to transform the RS signal into relevant ecological indicators. In this work, we provide the first results of a new international project aimed to re-analize archived RS data to study ecological changes in Lake Baikal and incorporate near-real time RS data to monitoring

  8. Altitudinal distributions of BDE-209 and other polybromodiphenyl ethers in high mountain lakes

    Bartrons, Mireia [Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona, 18, 08034 Barcelona, Catalonia (Spain); Limnology Unit (CSIC-UB), Centre for Advanced Studies of Blanes (CEAB-CSIC), Acces Cala St. Francesc, 14, 17300 Blanes, Catalonia (Spain); Grimalt, Joan O., E-mail: [Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona, 18, 08034 Barcelona, Catalonia (Spain); Catalan, Jordi [Limnology Unit (CSIC-UB), Centre for Advanced Studies of Blanes (CEAB-CSIC), Acces Cala St. Francesc, 14, 17300 Blanes, Catalonia (Spain)


    The present study shows the occurrence of 2,2',3,3',4,4',5,5',6,6'-decabromodiphenyl ether (BDE-209) in microbial biofilms of Pyrenean and Tatra high mountain lakes despite its low vapor pressure and high hydrophobicity. Aerosol air transport is therefore a feasible mechanism for BDE-209 accumulation in sites up to 2688 m above sea level. This compound and other PBDEs exhibit altitudinally-dependent distribution involving higher concentrations with increasing mountain lake elevation. However, the apparently very high enthalpies of the concentration gradients observed, including BDE-209, suggest that bacterial anaerobic debromination also plays a significant role in the resulting altitudinal distributions. This microbial mechanism explains the relative abundances of PBDEs and their within lake differences between rocky and sediment microbial biofilms, thereby showing that the altitudinal pattern observed is not purely due to water temperature control on bacterial activity but also to changes in the availability of anaerobic microenvironments which increase with increasing lake productivity at lower altitudes. - Highlights: > BDE-209 is found in high mountain areas despite its low vapor pressure. > Aerosol air transport may transport BDE-209 to high mountain sites. > BDE-209 and PBDEs exhibit altitudinally-dependent distributions. > PBDE bacterial anaerobic debromination is important in mountain areas. > Biodegradation may generate altitudinal and latitudinal concentration gradients. - Decabromodiphenyl ether and the other polybromodiphenyl congeners show vertical distributions in high mountains due to temperature effects and microbial degradation.

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

    Merkl, Sarah; Emmer, Adam; Mergili, Martin


    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

  10. Atmospheric deposition of polybromodiphenyl ethers in remote mountain regions of Europe

    L. Arellano


    Full Text Available Polybromodiphenyl ethers (PBDEs were analyzed in bulk atmospheric deposition collected in four European remote mountain areas over a period of two years (2004–2006: Lake Redon (Pyrenees, Gossenköllesee (Alps, Lochnagar (Grampian Mountains and Skalnate (Tatras. In all sites, the PBDE distributions were dominated by BDE209. BDE47 and BDE99 were the major low-brominated congeners, followed by BDE100 and BDE183. This composition is consistent with predominant inputs from the commercial mixtures decaBDE and pentaBDE. The total congener site-averaged fluxes ranged between 100 ng m−2 mo−1 (Alps and 190 ng m−2 mo−1 (Tatras. Significant correlations between PBDE deposition and percent of North Atlantic backwards air mass trajectories in the collected samples of the westernmost sites, Lochnagar and Redon, suggested an impact of transcontinental transfer of these pollutants from North American sources into Europe. Skalnate and, to a lower extent Redon, recorded another main PBDE source from central Europe corresponding to secondary emissions of the penta BDE commercial mixture. The fluxes of these secondary emissions were temperature dependent and correlated to total particle deposition and rainfall. Higher PBDE fluxes were observed at increasing temperature, particle deposition and precipitation. Another specific PBDE source was observed in United Kingdom and recorded in Lochnagar. Photolytic degradation during transport decreased the relative abundance of BDE209 and modified the emitted pentaBDE technical mixtures by depletion of the relative composition of BDE99 and, to a lower extent, BDE47. The transformations were more intense in the sites located above 2000 m, Redon and Gossenköllesee, and, particularly, during the warm periods.

  11. A comparison of remote sensing data sets for geothermal exploration over northern Fish Lake Valley, Nevada

    Littlefield, E. F.; Calvin, W. M.


    Remote sensing is a useful tool for identifying the surface expression of geothermal systems based on characteristic mineral assemblages that result from hydrothermal alteration. Hydrothermal alteration is often difficult to observe in the field; however associated minerals are spectrally distinct and can be identified using remote sensing data. In addition, remote sensing allows for classification of minerals over very large areas. Past studies have successfully mapped hydrothermal alteration over known systems in Nevada and California. Our group has provided detailed mineral mapping in several of these regions, as well as identifying thermal anomalies using aircraft and satellite sensors. We use a variety of multispectral (several wavelength channel) and hyperspectral (hundreds of wavelengths) data sets. These data sets are sensitive to surface mineralogy and lithology as well as surface temperature. This study compares the use of airborne instruments MASTER, AVIRIS, and SpecTIR for mineral identification across the large geographic area of Fish Lake Valley in Esmeralda County, Nevada. Details on the spatial and spectral resolution for each instrument are given in the table. This valley is a relatively unexplored geothermal center along the eastern flank of the White Mountains. The site shows up on GIS maps of “potential favorable development” and lies within a complicated pull-apart fault system. This area was also identified as a “top pick” for near-term development in a recent DOE study. There has been modest exploration in the region for geothermal resources and the area was awarded a GRED-III to the Esmeralda Energy Company. Previous drilling for mineral exploration and geothermal potential had indicated that a reservoir exists and seven deep wells have been drilled with maximum temperatures ranging up to 200C. The airborne spectral data over the northern Fish Lake Valley and adjacent Silver Peak Range were acquired between 2003 and 2008. The MASTER

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

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


    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.

  13. Remote sensing analysis of Lake Livingston aquatic plants

    Benton, A. R., Jr.; Newman, R. M.


    Results obtained during 1975 to monitor the growth of aquatic plants in the Lake Livingston area, using remote sensing photographic imagery, were described. Sequential total coverage was provided of the Jungle and White Rock Creek, plus coverage of smaller areas of localized infestation downlake, including Brushy Creek, KOA Kampground Marina, Penwaugh Slough, Memorial Point Marina, the Beacon Bay marinas and Pine Island. The imagery was generally good, photographic exposure being increased as the season progressed in order to obtain better pictures of the submerged vegetation. Some very significant differences in growth patterns, species interaction, and species dominance were observed when compared to 1974. Observation of the following plants was discussed: water hyacinth, hydrilla, coontail, potamageton. In general, the level of infestation was lower in 1975 than in 1974, due to the combined effect of more systematic application of herbicides and harsher intervening winter weather conditions.

  14. Chironomid communities as indicators of local and global changes in an oligotrophic high mountain lake (Enol Lake, Northwestern Spain

    Pol Tarrats


    Full Text Available The benthos of the high mountain Enol Lake (Picos de Europa National Park, Spain was analyzed in order to understand the spatiotemporal factors and patterns controlling its current Chironomidae community. In total, more than 14,000 chironomid larvae were identified, belonging to 27 taxa. The results have pointed out the presence of 3 main chironomid assemblages in the lake: i littoral community, which is mainly controlled by temperature and oxygen seasonal changes, ii Chara-dominant community, which is mainly controlled by the presence and abundance of Characeae in the lake, and iii profundal community, which is affected by low oxygen levels caused by sediment and organic matter discharge to the lake due to human pressures in the lake basin. We provide valuable insights for the managers to understand the current ecological status of Enol Lake and to evaluate which measures should be implemented to preserve or improve it. Moreover, our results constitute an essential step forward to improve the interpretation of the past changes of the lake by means of the subfossil chironomid community. 

  15. A new remote hazard and risk assessment framework for glacial lakes in the Nepal Himalaya

    Rounce, David R.; McKinney, Daene C.; Lala, Jonathan M.; Byers, Alton C.; Watson, C. Scott


    Glacial lake outburst floods (GLOFs) pose a significant threat to downstream communities and infrastructure due to their potential to rapidly unleash stored lake water. The most common triggers of these GLOFs are mass movement entering the lake and/or the self-destruction of the terminal moraine due to hydrostatic pressures or a buried ice core. This study initially uses previous qualitative and quantitative assessments to understand the hazards associated with eight glacial lakes in the Nepal Himalaya that are widely considered to be highly dangerous. The previous assessments yield conflicting classifications with respect to each glacial lake, which spurred the development of a new holistic, reproducible, and objective approach based solely on remotely sensed data. This remote hazard assessment analyzes mass movement entering the lake, the stability of the moraine, and lake growth in conjunction with a geometric GLOF to determine the downstream impacts such that the present and future risk associated with each glacial lake may be quantified. The new approach is developed within a hazard, risk, and management action framework with the aim that this remote assessment may guide future field campaigns, modeling efforts, and ultimately risk-mitigation strategies. The remote assessment was found to provide valuable information regarding the hazards faced by each glacial lake and results were discussed within the context of the current state of knowledge to help guide future efforts.

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

    Bernard J. COSBY


    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.

  17. Monitoring mountain lakes in a changing Alpine cryosphere: the Lago Nero project (Ticino, Switzerland)

    Scapozza, Cristian; Bruder, Andreas; Domenici, Mattia; Lepori, Fabio; Pera, Sebastian; Pozzoni, Maurizio; Rioggi, Stefano; Colombo, Luca


    Mountain lakes and their catchments of the Alpine cryosphere are facing global pressures including climate warming and deposition of atmospheric pollutants. Due to their remoteness, often low buffer capacities and sensitive biotic communities, alpine lake catchments are particularly well suited as sentinels of environmental change. Lago Nero is the object of an intensive survey, aimed at developing predictive models of catchment-wide ecosystem responses to environmental change (Bruder et al. 2016). Lago Nero is located at the head of Val Bavona (Canton Ticino, southern Switzerland), in a southwest-facing catchment, with altitude ranging from 2385 to 2842 m asl. The substrate is dominated by gneissic bedrock with patches of grassy vegetation and shallow soils. The catchment is snow-covered approximately from November to May. For a similar period, the lake is ice-covered. Lago Nero is an oligotrophic, soft-water lake with a surface of approximatively 13 ha and a maximal depth of 73 m. According to the regional model of potential permafrost distribution in the southern Swiss Alps (Scapozza & Mari 2010), the presence of discontinuous permafrost is probable in almost the entire surface of the catchment covered by loose debris. A direct evidence of permafrost occurrence is the presence of a small active/inactive rock glacier in the south-eastern part of the catchment (front altitude: 2560 m asl). Monitoring of the site began in summer 2014, with an initial phase aimed at developing and testing methodologies and at evaluating the suitability of the catchment and the feasibility of the monitoring program. The intensive survey at Lago Nero measures a wide array of ecosystem responses, including runoff quantity and chemistry, catchment soil temperature (also on the rock glacier) and composition of terrestrial vegetation. Sampling frequency depends on the parameter measured, varying from nearly continuous (e.g. runoff and temperature) to five-year intervals (e.g. soil and

  18. Spatiotemporal Variability of Lake Water Quality in the Context of Remote Sensing Models

    Carly Hyatt Hansen; Steven J Burian; Philip E Dennison; Gustavious P Williams


    This study demonstrates a number of methods for using field sampling and observed lake characteristics and patterns to improve techniques for development of algae remote sensing models and applications...

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

    Gunkel, Günter


    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.

  20. Rocky Mountain Arsenal Lower Derby Lake shoreline expansion project

    US Fish and Wildlife Service, Department of the Interior — The purpose of this Project Completion Report is to document the completion of the Lower Derby Lake Shoreline Expansion Project and summarize project highlights....

  1. Remote sensing for environmental protection of the eastern Mediterranean rugged mountainous areas, Lebanon

    Khawlie, M.; Awad, M.; Shaban, A.; Bou Kheir, R.; Abdallah, C.

    Lying along the eastern Mediterranean coast with elevated mountain chains higher than 2500 m straddling its terrain, Lebanon is a country of natural beauty and is thus attracting tourism. However, with a population density exceeding 800/km 2 and a rugged steep sloping land, problems abound in the country calling for holistic-approach studies. Only remote sensing, whose use is new in Lebanon can secure such needed studies within a scientific and pragmatic framework. The paper demonstrates for the concerned themes, the innovative use of remote sensing in such a difficult terrain, giving three examples of major environmental problems in the coastal mountains. Only few studies have so far focused on those mountains, notably application of remote sensing. The rugged mountainous terrain receives considerable rain, but the water is quickly lost running on the steep slopes, or infiltrating through fractures and the karstic conduits into the subsurface. Field investigations are difficult to achieve, therefore, remote sensing helps reveal various surface land features important in reflecting water feeding into the subsurface. Optical, radar and thermal infrared remotely sensed data cover a wide spectrum serving that purpose. A map of preferential groundwater accumulation potential is produced. It can serve for better water exploitation as well as protection. Because the terrain is karstic and rugged, the subsurface water flow is difficult to discern. Any pollution at a certain spot would certainly spread around. This constitutes the second example of environmental problems facing the mountainous areas in Lebanon. An integrated approach using remote sensing and geographic information systems (GIS) gives good results in finding out the likelihood of how pollution, or contaminants, can selectively move in the subsurface. A diagnostic analysis with a GIS-type software acts as a guide producing indicative maps for the above purpose. The third example given deals with the problem

  2. Lake Storage Change Automatic Detection by Multi-source Remote Sensing without Underwater Terrain Data

    ZHU Changming


    Full Text Available Focusing on lake underwater terrain unknown and dynamic storage that is difficult to obtain by the traditional methods, a new method is proposed for lake dynamic storage estimation by multi-source and multi-temporal remote sensing without underwater terrain data. The details are as follows. Firstly, extraction dynamic lake boundary through steps by steps adaptive iteration water body detection algorithm from multi-temporal remote sensing imagery. And then, retrieve water level information from ICESat GLAS laser point data. Thirdly, comprehensive utilizing lake area and elevation data, the lake boundary is converted to contour of water by the water level is assigned to the lake boundary line, according to the time and water level information. Fourthly, through the contour line construction TIN (triangulated irregular network model and Kriging interpolation, it is gotten that the simulated three-dimensional lake digital elevation model. Finally, on the basis of simulated DEM, it is calculated that the dynamic lake volume, lake area distribution and water level information. The Bosten lake is selected as a case studying to verify the algorithm. The area and dynamic water storage variations of Bosten lake are detected since 2000. The results show that, the maximum error is 2.21× 108 m3, the minimum error is 0.00002× 108 m3, the average error is 0.044×108 m3, the root mean square is 0.59 and the correlation coefficient reached 0.99.

  3. Drainage events from a glacier-dammed lake, Bear Glacier, Alaska: Remote sensing and field observations

    Wilcox, A. C.; Wade, A. A.; Evans, E. G.


    We investigated drainage events from a glacier-dammed lake on Bear Glacier, Alaska, and associated outburst floods and hazards. The glacier-dammed lake, which we call Ice Lake, is 17.5 km up-glacier from Bear Glacier's terminus at Bear Glacier Lake. We combine field observations and remote sensing to examine temporal changes in the size of Ice Lake, the frequency and timing of its drainage, and down-glacier propagation of its outburst floods. We found that in recent years, Ice Lake has likely drained every year or two, in late summer or fall (August-October), with outbursts generally following the damming of sufficient water to create a lake area of between 0.35 and 0.5 km2. Ice Lake has migrated downvalley to the south since the 1990s, likely as a result of thinning of the glacier that dams it. In situ measurements of a drainage event in October 2010 showed that Ice Lake drained over a period of days, which manifested at Bear Glacier Lake as a gradual, multiday increase and then decrease in water levels. Glacial lake outburst flooding at Bear Glacier creates risks for sea kayakers in Bear Glacier Lake and may be relevant to understanding the effects of climate warming on glacier-dammed and proglacial lakes.


    Gheorghe ROMANESCU


    Full Text Available In order to study the lake wetlands in the Central Group of the East Carpathian Mountains, we have chosen 6 anthropic lakes and 3 natural ones. The lake wetlands develop mainly in the area upstream the lake tail, at the outlet of the main watercourses. The most developed wetland areas can be found in Roşu Lake, at the mouth of the rivulets Licaş and Suhard, and in the area of Crucii Lake, appeared recently following a landslide. The dominant herbaceous vegetation is made up of bulrush, reeds and wetlands lawns, while the tree vegetation is made up of alders, willows and poplars.

  5. Interim report on pesticide levels in fish collected 20 March 1975 from Lake Ladora at Rocky Mountain Arsenal

    US Fish and Wildlife Service, Department of the Interior — Report on pesticide levels from fish taken from Lake Ladora at the Rocky Mountain Arsenal in March 1975. Fish were then sent to the Dugway Proving Grounds for...

  6. Monitoring the frozen duration of Qinshai Lake using satellite passive microwave remote sensing low frequency data

    CHE Tao; LI Xin; JIN Rui


    The Qinghai Lake is the largest inland lake in China.The significant difference of dielectric properties between water and ice suggests that a simple method of monitoring the Qinghai lake freeze-up and break-up dates using satellite passive microwave remote sensing data could be used.The freeze-up and break-up dates from the Qinghai Lake hydrological station and the MODIS L1B reflectance data were used to validate the passive microwave remote sensing results.The validation shows that passive microwave remote sensing data can accurately monitor the lake ice.Some uncertainty comes mainly from the revisit frequency of satellite overpass.The data from 1978 to 2006 show that lake ice duration is reduced by about 14-15 days.The freeze-up dates are about 4 days later and break-up dates about 10 days earlier.The regression analyses show that,at the 0.05 significance level,the correlations are 0.83,0.66 and 0.89 between monthly mean air temperature (MMAT) and lake ice duration days,freeze-up dates,break-up dates,respectively.Therefore,inter-annual variations of the Qinghai Lake ice duration days can significantly reflect the regional climate variation.

  7. Advances in Remote Sensing for Assessing High Altitude Glacio-Hydrology - with a Focus on High Mountain Asia

    Bolch, T.


    Meltwater released by glaciers can be of high importance for the overall run-off and thus affect society and development of mountainous regions and their forelands. However, glaciers are mostly located in harsh and remote environment and detailed in-situ measurements are impossible or limited to few glaciers. This lack of measurements of glacier characteristics (e.g. area, debris cover, flow) and mass budgets hampers a correct glacio-hydrologic modelling and representation of processes in advanced simulation models. Remote sensing has been proven a powerful tool in providing essential data to fill this gap. The most basic information in this respect is the location and area of the glaciers. A global and some regional inventories exist, but the uncertainties and differences among them are high, especially with respect to the upper accumulation area and debris cover. I here present a multi-method approach to map glaciers more precisely based on remote sensing data and combining image ratioing (using visible, infrared and thermal bands), micro-wave coherence images, terrain analysis, differencing of digital elevation models (DEMs) and, if available, high resolution images. DEM differencing is used to provide region-wide mass balance assessments, but volume to mass conversion and data voids introduce uncertainties. For High Mountain Asia (HMA), a crucial region in terms of water resources and glacier changes, most studies concentrate on the period after the year 2000 with the SRTM-DEM as baseline data set. However, declassified satellite data from the 1960s and 1970s also exist and allowed to extend the data record back in time for several regions in HMA. Using an example from an ice-covered area of ~5000 km² in the Aksu-Tarim catchment in Central Tien Shan the importance of remote sensing for glacio-hydrological modelling is shown. This is especially true for debris-covered and surge-type glaciers whose reaction to climate is still not fully understood. Therefore

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

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


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

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

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


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

  10. Light absorption by phytoplankton in the southern Baltic and Pomeranian lakes: mathematical expressions for remote sensing applications

    Justyna Meler


    The relationships derived here are applicable in local remote sensing algorithms used for monitoring the Baltic Sea and coastal lakes and can substantially improve the accuracy of the remotely determined optical and biogeochemical characteristics of these waters.

  11. 近期亚洲中部高山地区湖泊变化的时空分析%Spatio-temporal Analysis of Recent Changes of Lake Area and Lake Water Level at High Mountains in Central Asia

    李均力; 方晖; 包安明; 杨辽


    Inland lakes are major surface water resources in arid regions of Central Asia. They provide sparsely distributed but valuable fresh water resources for the fragile environments and human activities, which act as the essential components of the hydrological cycle and local ecosystems. Lakes in alpine regions are sensitive to natural changes, which can serve as an important indicator of global climate change and regional environment variations. Lake changes are mainly manifested by their level or area changes, which can provide evidence of spatial and temporal characteristics of regional water resource changes. Mapping these lakes and detecting their changes are therefore of great significance to understand the relevance of lake variations to climate changes, and they are also crucial to evaluating impacts of economic development on ecological balances. However, lake studies in these remote mountainous areas seem to be limited due to low accessibility and lack of observation data. Satellite remote sensing provides an efficient tool to analyze the status and variations in these lakes. In this paper, Landsat/CBERS were used to map lake area changes, and Jason, ICEsat/GLAS were employed to extract lake level information, forming a time series of level and area changes of 16 lakes over the past ten years. The spatial and temporal characteristics of lake level changes were also analyzed with information on glaciers and dams, so as to unravel the responses of level and area changes of different types of lakes to climate change and human activities. It is shown that remote sensing has a good performance of mapping lake level and area changes, and lake levels in October have good performance of describing the temporal processes of lake level changes. Glaciers are vital to alpine closed lakes, and the characteristics of level changes are classified into two modes based on glacier distribution: lakes in the northern Tibetan Plateau (the Kunlun Mountains, Karakorum

  12. Spatiotemporal Variability of Lake Water Quality in the Context of Remote Sensing Models

    Carly Hyatt Hansen


    Full Text Available This study demonstrates a number of methods for using field sampling and observed lake characteristics and patterns to improve techniques for development of algae remote sensing models and applications. As satellite and airborne sensors improve and their data are more readily available, applications of models to estimate water quality via remote sensing are becoming more practical for local water quality monitoring, particularly of surface algal conditions. Despite the increasing number of applications, there are significant concerns associated with remote sensing model development and application, several of which are addressed in this study. These concerns include: (1 selecting sensors which are suitable for the spatial and temporal variability in the water body; (2 determining appropriate uses of near-coincident data in empirical model calibration; and (3 recognizing potential limitations of remote sensing measurements which are biased toward surface and near-surface conditions. We address these issues in three lakes in the Great Salt Lake surface water system (namely the Great Salt Lake, Farmington Bay, and Utah Lake through sampling at scales that are representative of commonly used sensors, repeated sampling, and sampling at both near-surface depths and throughout the water column. The variability across distances representative of the spatial resolutions of Landsat, SENTINEL-2 and MODIS sensors suggests that these sensors are appropriate for this lake system. We also use observed temporal variability in the system to evaluate sensors. These relationships proved to be complex, and observed temporal variability indicates the revisit time of Landsat may be problematic for detecting short events in some lakes, while it may be sufficient for other areas of the system with lower short-term variability. Temporal variability patterns in these lakes are also used to assess near-coincident data in empirical model development. Finally, relationships

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

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


    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.

  14. Bringing the outside world to the remote mountains:the Nepal wireless networking project

    Sein, Maung,; Thapa, Devinder; Säbö, Öystein


    This teaching case presents the story of the Nepal Wireless Networking Project (NWNP) and its effort to connect villages in remote areas of Nepal to the outside world. Despite lack of access to proper equipment, the fact that it was illegal to install wireless network, lack of technical competence and the difficult terrain in the Himalayan mountains, Mahabir Pun, the initiator of NWNP, suceeded in bringing Internet access to these villages which led to improvement in education, health service...

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

    Buytaert, Wouter; De Bièvre, Bert


    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

  16. Ecological dynamics of two remote alpine lakes during ice-free season

    Rocco Tiberti


    Full Text Available We studied hydrochemistry and plankton dynamics in two remote alpine lakes: lake Nivolet superiore (2530 m asl and lake Trebecchi superiore (2729 m asl in the Gran Paradiso National Park (Western Italian Alps in summer 2009. The aim of this study was to enhance the understanding of natural ecological dynamics in the pelagic habitat of alpine lakes by enlarging the number of biotic and abiotic variables usually considered to this end and by increasing the frequency of samplings, generally low in remote lakes. During the eight samplings performed in 2009, chemical and physical variables were measured both in situ and in the laboratory. We also followed the dynamics of all the compartments of the naturally simplified trophic chain of the two lakes from pico-prokaryotes to phytoplankton and zooplankton. Our results confirm the oligotrophic, close-to-pristine state of lake Nivolet and lake Trebecchi as they are not affected by hydromorphological alterations, they are naturally fishless and are not sensitive to acidification risk and acidity pulses. On the other hand, the two lakes have distinct abiotic conditions due to their glacial origin and to the lithological composition of their watersheds. We found some differences in the spatial variation of pico-prokaryotes, phytoplankton and zooplankton due to the different mixing regimes and maximum depth of the two lakes. Conversely, temporal patterns were similar in both lakes, related to ecological interactions and to changes in the abiotic conditions. The rapid succession of events in extreme ecosystems, such as the alpine lakes studied here, confirm the predominant role of external environmental factors (e.g. the duration of the ice-free season and of ecological interactions among different trophic compartments. This research underlines the importance of seasonal niche partitioning among organisms with different size.

  17. Development of remote sensing tools to improve understanding and management of Lake Malawi

    Chavula, Geoffrey Mudolole

    Degradation of land resources in the drainage basin of Lake Malawi and other lakes of the African Rift Valley has been widespread over the past several decades. Causes for this degradation include inappropriate agricultural practices, indiscriminate disposal of wastes, and increasing population pressure. These factors pose serious threats to water quality in these important lakes. It is difficult and costly to monitor relevant water quality conditions, such as concentrations of chlorophyll-alpha in these large lakes using ground-based methods, and consequently, information on temporal and spatial variations in water quality conditions of these water bodies is quite limited. Methods that use satellite-based remote sensing data to infer lake clarity and chlorophyll levels have been developed in recent years and have potential for alleviating the problem of inadequate water monitoring data in large lakes in poor and developing countries. In addition to providing data on water quality and trophic state conditions of lakes, satellite imagery has potential for determining water circulation patterns in lakes through maps of lake surface temperature (LST). In turn, LST can be used to locate upwelling zones that may enhance commercial fishing in large deep lakes. Satellite imagery also may be used to characterize and map land use and land cover (LULC). Such information can serve as a basis for studies of the relationships between changes in LULC and lake conditions, such as lake level and water quality. This paper describes results of research to develop remote sensing tools to improve the understanding and management of Lake Malawi. It includes three major components, namely: estimating chlorophyll-alpha concentrations in Lake Malawi from MODIS/Terra satellite imagery; assessing the accuracy of existing split-window algorithms to estimate lake surface temperature from AVHRR and MODIS/Terra satellite data; and determining trends in forest cover and other categories of land

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

    Laney, R.L.


    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

  19. Estrogenic activity associated with organochlorine compounds in fish extracts from European mountain lakes

    Garcia-Reyero, Natalia [Institut de Biologia Molecular de Barcelona (CSIC), Jordi Girona 18, 08034 Barcelona, Catalonia (Spain); Grimalt, Joan O. [Institut d' Investigacions Quimiques i Ambientals de Barcelona (CSIC), Jordi Girona 18, 08034 Barcelona, Catalonia (Spain)]. E-mail:; Vives, Ingrid [Institut d' Investigacions Quimiques i Ambientals de Barcelona (CSIC), Jordi Girona 18, 08034 Barcelona, Catalonia (Spain); Fernandez, Pilar [Institut d' Investigacions Quimiques i Ambientals de Barcelona (CSIC), Jordi Girona 18, 08034 Barcelona, Catalonia (Spain); Pina, Benjamin [Institut de Biologia Molecular de Barcelona (CSIC), Jordi Girona 18, 08034 Barcelona, Catalonia (Spain)


    Fish muscle extracts from ten European mountain lakes were analyzed for organochlorine compounds (OCs) and estrogenic activity, the latter by a recombinant yeast assay based on the human estrogen receptor. Seventy percent of the samples showed estrogenic activity above detection limits and a subset of five samples showed estrogenic activities, equivalent to more than 10,000 pg/g of estradiol. These highly estrogenic samples occurred in two lakes, Velke Hincovo in the Tatra Mountains and Redon in the Pyrenees. Principal component analysis correlated estrogenic activity of muscle extracts to fish age and concentrations of the more chlorinated polychlorobiphenyls (PCBs). This is consistent with previously observed correlations of these PCBs with fish age. In addition, most fish with high estrogenic activity were found in lakes containing high OC levels in the sediments, which gives further ground to atmospheric deposition of anthropogenic pollutants as main process leading to the observed endocrine disruption effects. - Estrogen receptor agonists in lake fish are correlated with organochlorine compound content.

  20. Remote Sensing as a Tool to Track Algal Blooms in the Great Salt Lake, Utah, USA

    Bradt, S. R.; Wurtsbaugh, W. A.; Naftz, D.; Moore, T.; Haney, J.


    The Great Salt Lake is a large hypersaline, terminal water body in northern Utah, USA. The lake has both a significant economic importance to the local community as a source of brine shrimp and mineral resources, as well as, an ecological importance to large numbers of migratory waterfowl. Due to nutrient input from sewage treatment plants, sections of the Great Salt Lake are subjected to highly eutrophic conditions. One of the main tributaries, Farmington Bay, experiences massive blooms of cyanobacteria which can reach concentrations in excess of 300 mg l-1 in the bay. Effects of these blooms can be observed stretching into the rest of the lake. The detrimental outcomes of the blooms include unsightly scums, foul odor and the danger of cyanobacterial toxins. While the blooms have an obvious effect on Farmington Bay, it is quite possible that the cyanobacteria impact a much wider area of the lake as currents move eutrophic water masses. Of particular interest is the reaction of brine shrimp to the plumes of cyanobacteria-rich water leaving Farmington Bay. We are employing remote sensing as a tool to map the distribution of algae throughout the lake and produce lake-wide maps of water quality on a regular basis. On-lake reflectance measurements have been coupled with MODIS satellite imagery to produce a time series of maps illustrating changes in algal distribution. The successes and shortcomings of our remote sensing technique will be a central topic of this presentation.

  1. Assessment of nutrient distributions in Lake Champlain using satellite remote sensing.

    Isenstein, Elizabeth M; Park, Mi-Hyun


    The introduction of nutrients to lakes causing eutrophic conditions is a major problem around the world. Proper monitoring and modeling are important to effectively manage eutrophication in lake waters. The goal is to develop remote sensing models for nutrients, total phosphorus and total nitrogen, in Lake Champlain. The remote sensing models were created using multivariate linear regression with the unique band combinations of Landsat Enhanced Thematic Mapper Plus (ETM+) imagery based on the empirical relationship with the field observations. The resulting models successfully showed nutrient distributions in the most eutrophic part of Lake Champlain, Missisquoi Bay, with reasonable adjusted coefficient of determination values (R(2)=0.81 and 0.75 for total phosphorus and total nitrogen, respectively). The results show the feasibility and the utility of satellite imagery to detect spatial distributions of lake water quality constituents, which can be used to better understand nutrient distributions in Lake Champlain. This approach can be applicable to other lakes experiencing eutrophication assisting decision making when implementing Best Management Practices and other mitigation techniques to lakes. Copyright © 2014. Published by Elsevier B.V.

  2. Microplastic pollution of lakeshore sediments from remote lakes in Tibet plateau, China.

    Zhang, Kai; Su, Jing; Xiong, Xiong; Wu, Xiang; Wu, Chenxi; Liu, Jiantong


    Tibetan Plateau is known as the world's third pole, which is characterized by a low population density with very limited human activities. Tibetan Plateau possesses the greatest numbers of high-altitude inland lakes in the world. However, no information is currently available on the characteristic of microplastic pollution in those lakes within this remote area. In this work, lakeshore sediments from four lakes within the Siling Co basin in northern Tibet were sampled and examined for microplastics (plastic products. Polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyvinyl chloride were identified from the microplastic samples using laser Raman spectroscopy, and oxidative and mechanical weathering textures were observed on the surface of microplastics using scanning electron microscope. These results demonstrate the presence of microplastics even for inland lakes in remote areas under very low human impact, and microplastic pollution can be a global issue.

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

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


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

  4. Remote sensing of algal blooms by aircraft and satellite in Lake Erie and Utah Lake

    Strong, A. E.


    During late summer, when the surface waters of Lake Erie reach their maximum temperature, an algal bloom is likely to develop. Such phenomena, which characterize eutrophic conditions, have been noticed on other shallow lakes using the Earth Resources Technology Satellite (ERTS-1). The concentration of the algae into long streamers provides additional information on surface circulations. To augment the ERTS Multispectral Scanner Subsystem data of Lake Erie, an aircraft was used to obtain correlative thermal-IR and additional multiband photographs. A large bloom of Aphanizomenon flos-aquae observed in Utah Lake together with recent bloom history in Lake Erie is used to verify the Great Lakes bloom.


    BO Li-qun; ZHAO Yun-ping; HUA Ren-kui


    Volcanic eruption is one of the most serious geological disasters, however, a host of facts have proven that the Changbai Mountains volcano is a modem dormant one and has ever erupted disastrously. With the rapid development of remote sensing technology, space monitoring of volcanic activities has already become possible, particularly in the application of thermal infrared remote sensing. The paper, through the detailed analysis of geothermal anomaly factors such as heat radiation, heat conduction and convection, depicts the monitoring principles by which volcano activities would be monitored efficiently and effectively. Reasons for abrupt geothermal anomaly are mainly analyzed, and transmission mechanism of geothermal anomaly in the volcanic regions is explained. Also, a variety of noises disturbing the transmission of normal geothermal anomaly are presented. Finally, some clues are given based on discussing thermal infrared remote sensing monitoring mechanism toward the volcanic areas.

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

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


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

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

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


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

  8. Atmospheric deposition and lake chemistry trends at a high mountain site in the eastern Alps

    Bertha THALER


    Full Text Available Records of atmospheric precipitation chemistry starting in 1983 and a series of limnological investigations at two high mountain reference lakes starting in 1988 enable us to describe the response of lake water chemistry to changes in precipitation chemistry and climate. The lakes are located at an altitude well above the timberline in a watershed composed of acidic rocks. Despite the observed reduction in the sulphur atmospheric deposition, the reference lakes showed no corresponding decline in sulphate concentrations, but a marked increase in the acid neutralising capacity was apparent. Changes of the seasonal distribution pattern of the precipitation amounts and a general increase of the air temperature have likely produced an increased weathering which increased the concentration of many inlake solutes and drove the lakes toward more buffered conditions. This phenomenon superimposed to changes like other physical factors (radiation, nutritional conditions and biological factors (enhanced production, competition, predation has produced in the last years greater modifications than merely those to be expected from the decreased acidic input.

  9. Macrophytes assemblages in mountain lakes of Alerce Andino National Park (41° S, Lakes Region, Chile.

    Enrique Hauenstein


    Full Text Available The lakes studied (Chapo, Sargazo, Chaiquenes and Triángulo are located in the Alerce Andino National Park (41°30'S, 71°32'W, Chile. An inventory of the aquatic and riparian species was performed between December 2010 and January 2011. A null model analysis was done to determine the existence of regulatory factors of species associations, and the Jaccard index was applied to determine floristic similarities. It identidied 23 species, the high number was reported (14 and the most introduced species number (4 were reported at Sargazo lake, whereas the low species number was observed in Triángulo lake with three species. The analysis of the null model revealed the presence of regulatory factors in one of the three simulations. However, in the other two simulations, the species associations appeared to be random, presumably because many species were repeated at the study sites. According to the Jaccard index, Triángulo Lake is noticeably different from the other lakes, probably due to its marked oligotrophy.

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

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


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

  11. Using Hyperspectral Aircraft Remote Sensing to Support Ecosystems Services Research in New England Lakes and Ponds

    Keith, D. J.; Milstead, B.; Walker, H.; Worthy, D.; Szykman, J.; Wusk, M.; Kagey, L.; Howell, C.; Snook, H.; Drueke, C.


    Northeastern lakes and ponds provide important ecosystem services to New England residents and visitors. These include the provisioning of abundant, clean water for consumption, agriculture, and industry as well as cultural services (recreation, aesthetics, and wilderness experiences) which enhance local economies and quality of life. Less understood, but equally important, are the roles that these lakes play in protecting all life through supportive services such as nutrient cycling. Nitrogen and phosphorus have a direct impact on the condition of fresh water lakes. Excesses of these nutrients can lead to eutrophication, toxic cyanobacteria blooms, decreased biodiversity, and loss of ecosystem function leading to a reduction in the availability and delivery of ecosystem services. In this study, we examined how variations in lake nutrient concentrations and phytoplankton pigment concentrations correlated with changes in the potential to provide cultural ecosystem services. Using a NASA Cessna 206 aircraft, hyperspectral data were collected during late summer 2009 from 55 lakes in New Hampshire, Massachusetts, Connecticut, and Rhode Island over a 2 day period. From the spectral data, algorithms were created which estimated concentrations of chlorophyll a, phycocyanin, and colored dissolved organic matter. The remotely sensed estimates were supplemented by in situ chlorophyll a, total nitrogen, total phosphorus and lake color data from 43 lakes sampled by field crews from the New England states. The purpose of this research is to understand how variations in lake nutrient concentrations and phytoplankton pigment concentrations correlate with changes in availability of cultural ecosystem services in the surveyed lakes. This dataset will be combined with information from the EPA National Lake Survey (2007), the EPA New England Lakes and Ponds Survey (2008) and the USGS SPARROW model to explore the association between lake condition and the provisioning of ecosystem

  12. Nitrogen stable isotopes of ammonium and nitrate in high mountain lakes of the Pyrenees

    M. Bartrons


    Full Text Available Nitrogen stable isotopes (δ15N are increasingly used to trace food web relationships and the flow of matter in lakes. However, there is high variability in δ15N among primary producers and other primary energy resources that can eventually propagate throughout the lake food web. To increase our understanding of the origin of this variability, we measured ammonium and nitrate δ15N in atmospheric deposition (AD, epilimnetic water (EW, deep chlorophyll maximum water (DCMW, and sediment porewater (SPW in eight mountain lakes. A general δ15N (−3.4‰ for AD was estimated as the signature for AD ammonium and nitrate did not differ. All lakes showed similar high δ15N-NH4+ values for SPW (ca. 2.2‰. In contrast, the variability among lakes in water column values was high, although differences between EW and DCMW within a lake were low. δ15N-NO3- correlated with the altitude of the lakes, and its variability was interpreted as the influence of catchment nitrification, which is higher in talus landscapes. δ15N-NH4+ distribution had two modes, positive values (ca. 3‰ were associated to DCMW of shallow lakes, and probably reflect the SPW influence. Lower values (ca. −3‰ occur in EW and DCMW of deep lakes, and its variability was related to the degree that NO3- was up taken by primary producers and recycled within the food-web when NH4+ availability was low compared to demand. Overall, altitude, lake depth and seasonal cumulative primary production largely explain the patterns of δ15N variability observed in nitrogen dissolved compounds.

  13. A consideration of potential confounding factors limiting chemical and biological recovery at Lochnagar, a remote mountain loch in Scotland

    Derek MUIR


    Full Text Available Lochnagar, a remote loch in the Grampian Mountains of Scotland is one of the most studied freshwater bodies in the UK. It represents a key site in a number of monitoring programmes and has become the UK’s 'flag-ship' mountain lake in various EU funded projects over the last 15 years. Palaeolimnological studies have revealed the extent and diverse provenance of atmospherically deposited pollution at the site and show that the loch began to acidify in the mid-19th century. However, despite abatement strategies dramatically reducing the emission and deposition of non-marine sulphate and trace metals since the 1970s, the loch pH shows little sign of recovery and full basin fluxes of, for example, Pb and Hg show no decline or even a continued increase. It is suggested that the lack of recovery from acidification over the last 15 years of monitoring results from the balancing of the decline in sulphate by increased nitrate, and that this increase is related to winter duration and severity. The lack of response by the sediment record to declines in metal deposition is thought to be due to a continuing input of previously deposited metals from the catchment. Hypotheses for these enhanced catchment inputs involve responses to a changing climate. Site specific climate reconstructions and predictions for the 21st century suggest an accelerated increase in temperature rise and increased winter precipitation and storminess. These predicted changes are likely to exacerbate the input of metals (and other stored pollutants from the catchment but higher temperatures may also help to promote recovery from acidification.

  14. Integrated Evaluation Model for Eco- Environmental Quality in Mountainous Region Based on Remote Sensing and GIS

    LI Ainong; WANG Angsheng; HE Xiaorong; FENG Wenlan; ZHOU Wancun


    Based on Remote Sensing (RS), Geographic Information System (GIS), and combining Principal Component Analysis, this paper designed a numerical integrated evaluation model for mountain eco-environment on the base of grid scale. Using this model, we evaluated the mountain eco-environmental quality in a case study area-the upper reaches of Minjiang River, and achieved a good result, which accorded well with the real condition. The study indicates that, the integrated evaluation model is suitable for multi-layer spatial factor computation, effectively lowing man's subjective influence in the evaluation process; treating the whole river basin as a system, the model shows full respect to the circulation of material and energy, synthetically embodies the determining impact of such natural condition as water-heat and landform, as well as human interference in natural eco-system; the evaluation result not only clearly presents mountainous vertical distribution features of input factors, but also provides a scientific and reliable thought for quantitatively evaluating mountain eco-environment.

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

    Peng Zhang


    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.

  16. Equatorial mountain lakes show extended periods of thermal stratification with recent climate change

    Neal Michelutti


    Full Text Available Climate change in the Andes has already affected phenology, glaciology, and other ecosystem attributes, and now threatens to alter long-standing fundamental limnological properties. In the equatorial Andes, most lakes have traditionally been described as having waters that circulate continuously (polymictic, with only rare episodes of stratification. This characterization, albeit based on relatively few studies, is widely accepted, despite accelerated regional warming over the past 30 years.Here, we show that protracted periods of thermal stratification are presently the norm, not the exception, in equatorial mountain lakes. Annual circulation and stratification patterns recorded in four lakes from Ecuador’s southern Sierra show extended periods of stratification, which are stable and do not break down with nocturnal cooling. These data contrast with earlier research from this region, which reported full water column mixing and only infrequent stratification, but are not surprising in light of recent trends toward rising temperatures and declining wind velocities. Paleolimnological studies show that changes to the thermal regimes of these lakes likely began several decades ago and have resulted in ecosystem-scale changes including regime shifts in phytoplankton and declines in aquatic production.

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

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


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

  18. Investigation of lagoon lakes in Kocacay delta by using remote sensing method.

    Irtem, Emel; Sacin, Yener


    Coasts are areas that are under the influence of the interaction of the air, water and land and attract attention with the abundance of their natural resources and therefore are subjected to excessive usage. This excessive usage may disturb the sensitive balance of the coast ecosystem. In this study, the changes in Arapçiftligi, Poyraz, Dalyan lakes area found in Kocacay delta located in the south coast of Marmara sea was evaluated between the periods of 2000 to 2007 with remote sensing method. These lakes, located on the shores, have a very sensitive naturally dynamic balance and very importance in terms of natural surroundings and the coastal zones management plan. It must be known the change of the lakes mentioned above area according to years. Research and applications have demonstrated the advantages of remote sensing and geographic information system techiques on river,delta, lake, lagoon lake, sensitivite areas in a lakeshore, coastal erosion etc. monitoring and management. In the study, we benefited from Erdas and Intergraph-Geomedia 6.1 image processing and GIS, and also from AutoCAD 2007 and NetCAD 4.0 computer-aided design (CAD) software. For 2000, 2001, 2005 and 2007 years (4 number) Landsat-5 TM satellite images belonging to the region were used. As a result of the study, Arapçiftligi, Dalyan and Poyraz lake areas, number of islets that are seen in the lakes were given in respect to years. Arapçiftligi lake shrank 29.5% in size in the years 2000 and 2007. The fact that the lake continued to get smaller in size even in periods of high precipitation may be due to the sediment flowing from the agricultural fields established close to the lake area. Dalyan and Poyraz lakes lost 60% in terms of their surface area in the years 2000 and 2007. In 2000-2001 periods, Dalyan and Poyraz lakes increased in size by 3.2%. The reason for this could be the excessive precipitation and the fact that the seawater from Marmara sea seeps into the lake. Protection of the

  19. Microbial food web in an oligotrophic high mountain lake (Jöri Lake III, Switzerland

    Ferdinand SCHANZ


    Full Text Available Jöri Lake III (2512 m a.s.l., zm = 22 m, A = 57.81 ´ 103 m2, V = 601.1 ´ 103 m3 is situated in the Vereina region in the eastern part of the Swiss Alps. We studied microbial grazing on bacteria and bacterial productivity during the ice-free period. The lake normally gets thermally stratified for two months between July and September. In 1996, chlorophyll-a concentrations varied from 0.5 to 2.0 μg l-1 with maximum values just below the thermocline (6 m depth, in 1997, they were between 0.6 and 5.0 μg l-1 with maximum values at 10 m depth – several meters below the thermocline. Bacterial densities varied between 0.7 and 1.7 ´ 106 ml-1 with maxima in the thermocline, one to two meters above the chlorophyll maximum. The areal bacterial biomass (volume beneath 1 m2 to a depth of 8 m was 10 μg C l-1 which remained more or less constant for the periods investigated. In 1997, bacterial growth rate and production rates were determined using [3H]-thymidine incorporation. The rates were as low as 0.002 to 0.006 h-1 and 0.01 to 0.03 μg C l-1 h-1, respectively. We found a carbon ratio of bacteria, phytoplankton, and autotrophic picoplancton (APP of 1.5:1.1:1 which shows a rather high abundance of bacteria and autotrophic picoplankton (APP compared to larger phytoplankton. Bacterial growth followed a temperature dependence similar to the one observed for bacteria from Lake Zürich, a prealpine and mesotrophic lake which was studied for comparison. Microbial food web in Jöri Lake III was not top down controlled during the periods of our study and mixotrophic algae like Dinobryon cylindricum var. alpinum and autotrophic nanoflagellates (ANF were the dominant bacterial grazers observed.

  20. Planetary Lake Lander - A Robotic Sentinel to Monitor a Remote Lake

    Pedersen, Liam; Smith, Trey; Lee, Susan; Cabrol, Nathalie; Rose, Kevin


    The Planetary Lake Lander Project is studying the impact of rapid deglaciation at a high altitude alpine lake in the Andes, where disrupted environmental, physical, chemical, and biological cycles result in newly emerging natural patterns. The solar powered Lake Lander robot is designed to monitor the lake system and characterize both baseline characteristics and impacts of disturbance events such as storms and landslides. Lake Lander must use an onboard adaptive science-on-the-fly approach to return relevant data about these events to mission control without exceeding limited energy and bandwidth resources. Lake Lander carries weather sensors, cameras and a sonde that is winched up and down the water column to monitor temperature, dissolved oxygen, turbidity and other water quality parameters. Data from Lake Lander is returned via satellite and distributed to an international team of scientists via web-based ground data systems. Here, we describe the Lake Lander Project scientific goals, hardware design, ground data systems, and preliminary data from 2011. The adaptive science-on-the-fly system will be described in future papers.

  1. Macrophytes assemblages in mountain lakes of Alerce Andino National Park (41° S, Lakes Region, Chile).

    Enrique Hauenstein; Mario Romero Mieres; Patricio Acevedo


    The lakes studied (Chapo, Sargazo, Chaiquenes and Triángulo) are located in the Alerce Andino National Park (41°30'S, 71°32'W), Chile. An inventory of the aquatic and riparian species was performed between December 2010 and January 2011. A null model analysis was done to determine the existence of regulatory factors of species associations, and the Jaccard index was applied to determine floristic similarities. It identidied 23 species, the high number was reported (14) and the most introduced...

  2. A Fruit of Yucca Mountain: The Remote Waste Package Closure System

    Kevin Skinner; Greg Housley; Colleen Shelton-Davis


    Was the death of the Yucca Mountain repository the fate of a technical lemon or a political lemon? Without caution, this debate could lure us away from capitalizing on the fruits of the project. In March 2009, Idaho National Laboratory (INL) successfully demonstrated the Waste Package Closure System, a full-scale prototype system for closing waste packages that were to be entombed in the now abandoned Yucca Mountain repository. This article describes the system, which INL designed and built, to weld the closure lids on the waste packages, nondestructively examine the welds using four different techniques, repair the welds if necessary, mitigate crack initiating stresses in the surfaces of the welds, evacuate and backfill the packages with an inert gas, and perform all of these tasks remotely. As a nation, we now have a proven method for securely sealing nuclear waste packages for long term storage—regardless of whether or not the future destination for these packages will be an underground repository. Additionally, many of the system’s features and concepts may benefit other remote nuclear applications.

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

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


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

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

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


    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

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

    Jehan Ramdani Hariyati


    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

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

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


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

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

    Iturrizaga, Lasafam


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

  8. What affects the nitrogen retention in Tatra Mountains lakes' catchments in Poland?

    D. Rzychoń


    Full Text Available The study of acidification and recovery of two lakes situated in the Polish Tatra Mountains, exposed to similar deposition of acidic substances but differing in altitude, catchment morphology, hydrology, and biodiversity is presented. Measurements were performed in 1992–1996 and 2001–2005. Simultaneously, research on the atmospheric deposition was carried out. The following physical and chemical parameters in lake water and precipitation were measured: pH, conductivity (K25, Ca2+, Mg2+, Na+, K+, NH4+, SO42−, NO3, Cl and alkalinity. Distinct changes in the chemical composition of precipitation were observed over 14 years (1992–2005. During this time the sulphate concentration decreased significantly, and the concentration of hydrogen ions in precipitation decreased at an average rate of 2.23 meq/m³/yr. There was no significant change in nitrate, ammonium or total nitrogen deposition. The chemical composition of water of both lakes changed significantly and showed signs of chemical recovery with decreases in sulphate concentration and increases in acid neutralising capacity. The concentration of base cations declined. Despite the lack of clear trends in nitrogen deposition, a statistically significant drop in concentration was observed in the two lakes. A significant increase of about 15% in the retention of nitrogen compounds in both catchments occurred. An improvement in nitrogen saturation status in both catchments was observed. This probably resulted mainly from decreasing acidification and global warming which prolongs the vegetative period, changes plant species composition and increases the microbiological activity of soil.

  9. What affects the nitrogen retention in Tatra Mountains lakes' catchments in Poland?

    D. Rzychoń


    Full Text Available The study of acidification and recovery of two lakes situated in the Polish Tatra Mountains, exposed to similar deposition of acidic substances but differing in altitude, catchment morphology, hydrology, and biodiversity is presented. Measurements were performed in 1992–1996 and 2001–2005. Simultaneously, research on the atmospheric deposition was carried out. The following physical and chemical parameters in lake water and precipitation were measured: pH, conductivity (K25, Ca2+, Mg2+, Na+, K+, NH4+, SO42−, NO3, Cl and alkalinity. Distinct changes in the chemical composition of precipitation were observed over 14 years (1992–2005. During this time the sulphate concentration decreased significantly, and the concentration of hydrogen ions in precipitation decreased at an average rate of 2.23 meq/m3/yr. There was no significant change in nitrate, ammonium or total nitrogen deposition. The chemical composition of water of both lakes changed significantly and showed signs of chemical recovery with decreases in sulphate concentration and increases in acid neutralising capacity. The concentration of base cations declined. Despite the lack of clear trends in nitrogen deposition, a statistically significant drop in concentration was observed in the two lakes. A significant increase of about 15% in the retention of nitrogen compounds in both catchments occurred. An improvement in nitrogen saturation status in both catchments was observed. This probably resulted mainly from decreasing acidification and global warming which prolongs the vegetative period, changes plant species composition and increases the microbiological activity of soil.

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

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


    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

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

    Lazaridou, Maria A.; Karagianni, Aikaterini C.


    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.

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

    Fasil Degefu


    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

  13. Remote Sensing and GIS Application to Superlarge Mineral Deposits Prediction in Western Slope of Great Xing'an Mountains, China

    Chen Shengbo


    Supported by Geographic Information Systems (GIS), the multi - source geoscience information in the Western Slope of Great Xing' an Mountains are visual analyzed, including remote sensing data, magnetic data, gravity data and gamma - ray spectrometry data. Thus the structural framework is built up. And the remote sensing image pattern of mineral deposits is established by comparing the remote sensing geological features of five large or superlarge mineral deposits located in the same metallogenic belt in China, Russia and Mongolia. Guided by the image pattern, seven prospective locations of large or superlarge mineral resource are delineated.

  14. Remote sensing of the mountain cryosphere using texture filters and apparent thermal inertia

    Brenning, A.; Fieguth, P.; Long, S.; Peña, M. A.; Soliman, A. S.


    Rock glaciers and debris-covered glaciers on Earth, and analog landforms on Mars, constitute hidden water resources and components of the cryosphere that are difficult to map or characterize using remote sensors. We utilize two innovative approaches in this field, (1) texture filters and (2) thermal features, in particular apparent thermal inertia (ATI), in order to investigate ice-debris landforms and in particular rock glaciers in the semi-arid Andes. Even though the ridge-and-furrow surface patterns are probably the most characteristic morphological features of rock glaciers, our study is the first to apply texture filters to the problem of remotely-sensed rock glacier detection. Gabor filters are designed to detect zebra-like patterns and are therefore an obvious choice for this study. Texture features derived from a Gabor filterbank were calculated from panchromatic IKONOS orthoimagery and used to discriminate rock glacier and other debris surfaces utilizing four classification methods of varying complexity: generalized linear model (GLM), generalized additive model (GAM), support vector machine (SVM), and tree ensembles (Bundling). Bundling outperformed the other methods in most situations studied, achieving an area under the ROC curve (AUROC) of 0.72-0.80 in different spatial cross-validation scenarios. This study focused on a narrow area of interest that cannot be easily identified as non-rock glacier area based on topographic criteria, and therefore significantly better results are expected in practical mapping situations in combination with terrain attributes as predictors. Thermal remote sensing has been of limited use in mountain cryospheric studies. In addition to land surface temperature (LST), ATI is of particular interest in this context. Thermal inertia is a single thermophysical material property that determines the amplitude of temperature variations at the surface of a periodically heated half-space, and shows promise in discriminating different

  15. Remote Measurement of Heat Flux from Power Plant Cooling Lakes

    Garrett, Alfred J.; Kurzeja, Robert J.; Villa-Aleman, Eliel; Bollinger, James S.; Pendergast, Malcolm M.


    Laboratory experiments have demonstrated a correlation between the rate of heat loss q" from an experimental fluid to the air above and the standard deviation σ of the thermal variability in images of the fluid surface. These experimental results imply that q" can be derived directly from thermal imagery by computing σ. This paper analyses thermal imagery collected over two power plant cooling lakes to determine if the same relationship exists. Turbulent boundary layer theory predicts a linear relationship between q" and σ when both forced (wind driven) and free (buoyancy driven) convection are present. Datasets derived from ground- and helicopter-based imagery collections had correlation coefficients between σ and q" of 0.45 and 0.76, respectively. Values of q" computed from a function of σ and friction velocity u* derived from turbulent boundary layer theory had higher correlations with measured values of q" (0.84 and 0.89). Finally, this research may be applicable to the problem of calculating losses of heat from the ocean to the atmosphere during high-latitude cold-air outbreaks because it does not require the information typically needed to compute sensible, evaporative, and thermal radiation energy losses to the atmosphere.

  16. Dynamic modeling of the spatial distribution of precipitation in remote mountainous areas

    Barros, A.P.; Lettenmaier, D.P. (Univ. of Washington, Seattle (United States))


    Precipitation in remote mountainous areas dominates the water balance of many water-short areas of the globe, such as western North America. The inaccessibility of such environments prevents adequate measurement of the spatial distribution of precipitation and, hence, direct estimation of the water balance from observations of precipitation and runoff. Resolution constraints in atmospheric models can likewise result in large biases in prediction of the water balance for grid cells that include highly diverse topography. Modeling of the advection of moisture over topographic barriers at a spatial be sufficient to resolve the dominant topographic features offers one method of better predicting the spatial distribution of precipitation in mountainous areas. A model is described herein that simulates Lagrangian transport of moist static energy and total water through a 3D finite-element grid, where precipitation is the only scavenging agent of both variables. The model is aimed primarily at the reproduction of the properties of high-elevation precipitation for long periods of time, but it operates at a time scale (during storm periods) of 10 min to 1 h and, therefore, is also able to reproduce the distribution of storm precipitation with an accuracy that may make it appropriate for the forecasting of extreme events. The model was tested by application to the Olympic Mountains, Washington, for a period of eight years (1967-74). Areal average precipitation, estimated through use of seasonal and annual runoff, was reproduced with errors in the 10%-15% range. Similar accuracy was achieved using point estimates of monthly precipitation from snow courses and low-elevation precipitation gauges. 36 refs., 15 figs., 6 tabs.

  17. Contaminant loading in remote Arctic lakes affects cellular stress-related proteins expression in feral charr.

    Wiseman, Steve; Jorgensen, Even H.; Maule, Alec G.; Vijayan, Mathilakath M.


    The remote Arctic lakes on Bjornoya Island, Norway, offer a unique opportunity to study possible affect of lifelong contaminant exposure in wild populations of landlocked Arctic charr (Salvelinus alpinus). This is because Lake Ellasjoen has persistent organic pollutant (POP) levels that are significantly greater than in the nearby Lake Oyangen. We examined whether this differential contaminant loading was reflected in the expression of protein markers of exposure and effect in the native fish. We assessed the expressions of cellular stress markers, including cytochrome P4501A (Cyp1A), heat shock protein 70 (hsp70), and glucocorticoid receptor (GR) in feral charr from the two lakes. The average polychlorinated biphenyl (PCB) load in the charr liver from Ellasjoen was approximately 25-fold higher than in individuals from Oyangen. Liver Cyp1A protein expression was significantly higher in individuals from Ellasjoen compared with Oyangen, confirming differential PCB exposure. There was no significant difference in hsp70 protein expression in charr liver between the two lakes. However, brain hsp70 protein expression was significantly elevated in charr from Ellasjoen compared with Oyangen. Also, liver GR protein expression was significantly higher in the Ellasjoen charr compared with Oyangen charr. Taken together, our results suggest changes to cellular stress-related protein expression as a possible adaptation to chronic-contaminant exposure in feral charr in the Norwegian high-Arctic.

  18. Suitability of Lake Erie for bigheaded carps based on bioenergetic models and remote sensing

    Anderson, Karl R.; Chapman, Duane C.; Wynne, Timothy; Masagounder, Karthik; Paukert, Craig


    Algal blooms in the Great Lakes are a potential food source for silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis; together bigheaded carps). Understanding these blooms thus plays an important role in understanding the invasion potential of bigheaded carps. We used remote sensing imagery, temperatures, and improved species specific bioenergetics models to determine algal concentrations sufficient for adult bigheaded carps. Depending on water temperature we found that bigheaded carp require between 2 and 7 μg/L chlorophyll or between 0.3 and 1.26 × 105cells/mL Microcystis to maintain body weight. Algal concentrations in the western basin and shoreline were found to be commonly several times greater than the concentrations required for weight maintenance. The remote sensing images show that area of sufficient algal foods commonly encompassed several hundred square kilometers to several thousands of square kilometers when blooms form. From 2002 to 2011, mean algal concentrations increased 273%–411%. This indicates Lake Erie provides increasingly adequate planktonic algal food for bigheaded carps. The water temperatures and algal concentrations detected in Lake Erie from 2008 to 2012 support positive growth rates such that a 4 kg silver carp could gain between 19 and 57% of its body weight in a year. A 5 kg bighead carp modeled at the same water temperatures could gain 20–81% of their body weight in the same period. The remote sensing imagery and bioenergetic models suggest that bigheaded carps would not be food limited if they invaded Lake Erie.

  19. Pollen dispersal in a mountainous area based on pollen analysis of four natural trap types from Lugu Lake, southwest China

    Su-Ping LI; Ya-Qin HU; David Kay FERGUSON; Jian-Xin YAO; Cheng-Sen LI


    Palynological analysis of 24 samples from four types of natural pollen traps (Lugu Lake bottom sediments,surface soil,bark samples,and moss cushions) in four sites at different altitudes from the Lugu Lake area,southwest China,has been undertaken to investigate pollen dispersal and deposition in a mountainous area and assist with the interpretation of fossil pollen analysis.Detailed comparisons between the palynological assemblage and the modern vegetation in the Lugu Lake region have been carried out.Preliminary interpretations of the correlation between pollen assemblage and vegetation at the different vertical vegetational zones can be recognized by the percentages of the main taxa,and most of the pollen taxa except Pinus are expected to be underrepresented.Exotic pollen grains can be transported over mountains more than 70 km away by wind.Upslope or downslope transport of pollen grains is crucial when reconstructing palaeoclimate in mountainous areas.We summarize the altitudinal distributions of modern woody plants whose pollen grains are present at three sites,and reveal that pollen grains are more readily carried uphill than downhill.These findings have important implications regarding the reconstruction of vegetation in mountainous regions and the interpretion of palaeoelevations.

  20. Fish Diversity and Abundance of Lake Tanganyika: Comparison between Protected Area (Mahale Mountains National Park and Unprotected Areas

    Emmanuel A. Sweke


    Full Text Available High biodiversity is the most remarkable characteristic of Lake Tanganyika including vertebrates, invertebrates, and plants. A few protected areas have been created along the lake to protect its biodiversity. However, limited studies have been carried out to ascertain their effectiveness. The current study aimed at assessing and comparing fish diversity and abundance of Lake Tanganyika in a protected area (Mahale Mountains National Park (MMNP and unprotected areas surrounding it. The data were collected in the near shore zone at 5 m and 10 m depths using stationary visual census (SVC technique. The protected area recorded higher fish richness and abundance than unprotected areas (P<0.05. It was concluded that the protected area is effective in conserving the fish diversity and abundance of the lake. However, more studies should be carried out regularly to explore the efficacy of the protected area in conservation of aquatic biodiversity and abundance.

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

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


    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.

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

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


    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

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

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


    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 ( 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 (, its NASA GSFC partners (, 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

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

    Kun Xue


    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.

  5. 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

    A. A. Abdulmedzhidov


    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.

  6. Bathymetric evolution of Tasman Glacier terminal lake, New Zealand, as determined by remote surveying techniques

    Purdie, Heather; Bealing, Paul; Tidey, Emily; Gomez, Christopher; Harrison, Justin


    Processes that drive iceberg calving at the margins of freshwater terminating glaciers are still poorly understood. This knowledge-gap is in part due to the challenge of obtaining good in situ data in a highly dynamic and dangerous environment. We are using emerging remote technologies, in the form of a remote controlled jet boat to survey bathymetry, and Structure from Motion (SfM) to characterize terminus morphology, to better understand relationships between lake growth and terminus evolution. Comparison of results between the jet boat mounted dual-frequency Garmin fish-finder with an Odom Echotrac DF3200 MKII with 200/38 kHz dual-frequency transducer, showed that after a sound velocity adjustment, the remote survey obtained depth data within ± 1 m of the higher grade survey equipment. Water depths of up to 240 m were recorded only 100 m away from the terminus, and subaerial cliff height ranged from around 6 to 33 m, with the central region of the terminus more likely to experience buoyancy. Subaqueous ice ramps are ephemeral features, and in 2015 multiple ice ramps extended out into the lake from the terminus by 100-200 m. The consistent location of some of the subaqueous ramps between surveys may indicate that other processes, for example, subglacial hydrology, also influence evolving terminus morphology.

  7. Modeling of the Perito Moreno glacier damming events and water balance of Rico branch (Lake Argentino) based on remote sensing and in situ data

    Arsen, A.; Abarca del Rio, R.; Cretaux, J.; Calmant, S.


    Located in a mountainous area Lake Argentino is one of the biggest water bodies in South America. It's a tourist attraction well-known worldwide for extreme ice damming events due to the presence of the Perito Moreno glacier splitting the southernmost branch, known as Rico branch, from the main body of the Lake Argentino. In the present study our objective is to investigate if the water can be accumulated during damming not only by excess of precipitations but also by the accumulation process due to the closed passage between Rico and the main water body of Lake Argentino. This is achieved by establishing a simple model which estimates short term evolutions of Rico water balance. With our model we simulate Rico 2004, 2006, 2008 damming events for which altimetry data are available, theirs hydrological regimes and the amount of incoming and outgoing water to provide plausible explanation. Our simulations explain almost 100% of water present in the Rico system during each damming. Thus, by so doing this we can affirm that the damming of water can be driven not only by simple excess of inputs but also by closure of the passage between Rico branch and Lake Argentino. Moreover, by combining different remote sensing and in situ data we establish the hypsometry of Rico branch. We prove the existence of a small permanent flux of water between both parts of the lake and the possibility of the damming formation detection in in situ (or altimetry) measurements. Although very narrow size of Rico branch, the altimetry data processing from Envisat mission can provide time series of lake surface heights over both parts. Coupled with optical Landsat imaging, those results give possibility to evaluate only by remote sensing approach approximate water storage during ice damming events. Until now Envisat was the only mission which gave exploitable data over Rico, but recent scientific missions such as Cryosat-2 and AltiKa give new opportunities to study lakes water balance, and

  8. Retrieval study of lake water depth by using multi-spectral remote sensing in Bangong Co Lake

    Pu Zheng; ZhengDong Deng; Xin Ye


    This paper reviewed studies on remote sensing of water depth retrieval. Four water depth retrieval models (single-band, dou-ble-ratio-band, multi-band, and BP network models) were evaluated using TM image and water data from Bangong Co Lake, which is located in China’s Tibet Autonomous Region and Indian Kashmir. Tested by independent data, comparison of these four models demonstrates that BP network model performed better than the multi-band model, with the single-band model performing the worst. To sum up, this study demonstrates that first, BP network model performed better than the traditional model;second, precise atmospheric correction and radiation study, affected by different water level sand sediment, could improve the precision of water depth retrieval.

  9. Satellite remote sensing of water turbidity in Alqueva reservoir and implications on lake modelling

    M. Potes


    Full Text Available The quality control and monitoring of surface freshwaters is crucial, since some of these water masses constitute essential renewable water resources for a variety of purposes. In addition, changes in the surface water composition may affect the physical properties of lake water, such as temperature, which in turn may impact the interactions of the water surface with the lower atmosphere.

    The use of satellite remote sensing to estimate the water turbidity of Alqueva reservoir, located in the south of Portugal, is explored. A validation study of the satellite derived water leaving spectral reflectance is firstly presented, using data taken during three field campaigns carried out during 2010 and early 2011. Secondly, an empirical algorithm to estimate lake water surface turbidity from the combination of in situ and satellite measurements is proposed. Finally, the importance of water turbidity on the surface energy balance is tested in the form of a study of the sensitivity of a lake model to the extinction coefficient of water (estimated from turbidity, showing that this is an important parameter that affects the lake surface temperature.

  10. Remote sensing models using Landsat satellite data to monitor algal blooms in Lake Champlain.

    Trescott, A; Park, M-H


    Lake Champlain is significantly impaired by excess phosphorus loading, requiring frequent lake-wide monitoring for eutrophic conditions and algal blooms. Satellite remote sensing provides regular, synoptic coverage of algal production over large areas with better spatial and temporal resolution compared with in situ monitoring. This study developed two algal production models using Landsat Enhanced Thematic Mapper Plus (ETM(+)) satellite imagery: a single band model and a band ratio model. The models predicted chlorophyll a concentrations to estimate algal cell densities throughout Lake Champlain. Each model was calibrated with in situ data compiled from summer 2006 (July 24 to September 10), and then validated with data for individual days in August 2007 and 2008. Validation results for the final single band and band ratio models produced Nash-Sutcliffe efficiency (NSE) coefficients of 0.65 and 0.66, respectively, confirming satisfactory model performance for both models. Because these models have been validated over multiple days and years, they can be applied for continuous monitoring of the lake.

  11. The water chemistry of some shallow lakes in Northern Patagonia and their nitrogen status in comparison with remote lakes in different regions of the globe

    Rosario MOSELLO


    Full Text Available Eighteen small shallow lakes located in the Northern Patagonian Lake District, in southern South America, were sampled in 2001 and analysed for the main chemical variables (pH, conductivity, alkalinity, major ions and nutrients. The study lakes span a wide geographical and altitudinal range and belong partly to the Pacific and partly to the Atlantic watershed. The main aim of this study was to investigate the relationships between water chemistry and physical/geographical properties of these lakes. Secondly, the nitrogen content of the lakes was considered in detail, and results compared to those obtained in previous studies carried out in other remote areas of the globe (the Central Southern Alps in Italy, the Sierra da Estrela region in Portugal, the Svalbard Islands in the Arctic, the Khumbu-Himal region in Nepal, and the Terra Nova Bay area in Antarctica. In the Alps, lakes are characterised by markedly high nitrogen concentrations, manly as nitrate, due to the high inputs of nitrogen compounds from downwind sources like the Po Plain in Northern Italy. Conversely, lakes at remote locations such as the Andes, Antarctica and Himalaya are characterised by a low nitrogen content, mainly as organic nitrogen. This status is related to the limited atmospheric inputs of nitrogen affecting these regions.

  12. Biogenic and abiogenic polynuclear aromatic hydrocarbons in sediments from two remote Adirondack lakes

    Tan, Y. L.; Heit, M.


    Sediment cores from Sagamore Lake and Woods Lake in New York State's Adirondack Park, an area remote from industrial activities, were analyzed for polynuclear aromatic hydrocarbons (PAH) by high resolution gas chromatography/mass spectrometry (GC/MS). Their composition and distribution with depth in the sediment indicate that the parental PAH in the surface sediments are primarily produced by anthropogenic combustion of fossil fuels. Perylene in deep sediments is apparently transformed from natural precursors in the reducing environment, however, the exact precursors remain unknown. The rather even sediment distributions of the non-parental PAH differ from the parental, suggesting biogenic origins. Based on their chemical structures, retene and alkylated and partially hydrogenated phenanthrenes are believed to be biogenically converted from abietic acid; hydrochrysenes and hydropicenes, from pentacyclic triterpenes.

  13. Analysis of remote sensing data for geothermal exploration over Fish Lake Valley, Esmeralda County, Nevada

    Littlefield, Elizabeth F.

    The purpose of this study was to identify and map hydrothermal alteration and geothermal deposits in northern Fish Lake Valley, Nevada using both visible, near, shortwave infrared (0.4-2.5 microm) and thermal infrared (8-12 microm) remote sensing data. Visible, near, and shortwave infrared data were collected by four airborne instruments including NASA's Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and MODIS-ASTER (MASTER) instruments, HyVista Corporation's HyMap sensor, and SpecTIR Corporation's ProSpecTIR instrument. MASTER also collected thermal infrared data over Fish Lake Valley. Hydrothermal alteration minerals and hot spring deposits were identified using diagnostic spectra extracted from the remote sensing data. Mapping results were verified in the field using a portable spectrometer. Two areas of opaline sinter and travertine deposits were identified west of the Fish Lake Valley playa. Field observation reveals the alternating nature of these beds, which likely reflects fluctuating hot spring fluid chemistries. Sinter and travertine were likely deposited around fault-related hot springs during the Pleistocene when the water table was higher. Previously undiscovered Miocene crystalline travertine was identified within the Emigrant Hills near Columbus Salt Marsh. Argillic alteration was mapped in parts of the ranges surrounding Fish Lake Valley. Kaolinite, and to a lesser extent, muscovite and montmorillonite, were used as indicator minerals for argillic alteration. In these regions, thermal fluids were likely discharged from faults to alter rhyolite tuff. Mineral maps were synthesized with previously published geologic data and used to delineate four new targets for future geothermal exploration. The abundant hot spring deposits along the edge of the Volcanic Hills combined with argillic alteration minerals mapped in the ranges suggest geothermal influence throughout much of the valley.

  14. Quantitative remote sensing of ammonium minerals, Cedar Mountains, Esmeralda County, Nevada

    Baugh, William M.; Kruse, Fred A.


    Mineral-bound ammonium (NH4+) was discovered by the U.S. Geological Survey in the southern Cedar Mountains of Esmeralda County, Nevada in 1989. At 10 km in length, this site is 100 times larger than any previously known occurrence in volcanic rocks. The ammonium occurs in two hydrothermally altered, crystal-rich rhyolitic tuff units of Oligocene age, and is both structurally and stratigraphically controlled. This research uses Advanced Visible/Infrared Imaging Spectrometer (AVIRIS) data to quantitatively map the mineral-bound ammonium (buddingtonite) concentration in the altered volcanic rocks. Naturally occurring mineral-bound ammonium is fairly rare; however, it has been found to occur in gold-bearing hydrothermal deposits. Because of this association, it is thought that ammonium may be a useful too in exploration for gold and other metal deposits. Mineral-bound ammonium is produced when an ammonium ion (NH4+) replaces the alkali cation site (usually K+) in the crystal structure of silicate minerals such as feldspars, micas and clays. Buddingtonite is an ammonium feldspar. The ammonium originates in buried organic plant matter and is transported to the host rock by hydrothermal fluids. Ammonium alteration does not produce visible changes in the rock, and it is barely detectable with standard x-ray diffraction methods. It is clearly identified, however, by absorption features in short wave-infrared (SWIR) wavelengths (2.0 - 2.5 micrometers). The ammonium absorption features are believed to be caused by N-H vibrational modes and are analogous to hydroxyl (O-H) vibrational modes, only shifted slightly in wavelength. Buddingtonite absorption features in the near- and SWIR lie at 1.56, 2.02 and 2.12 micrometers. The feature at 2.12 micrometer is the strongest of the three and is the only one used in this study. The southern Cedar Mountains are sparsely vegetated and are an ideal site for a remote sensing study.

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

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


    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

  16. In-situ multispectral and bathymetric measurements over a supraglacial lake in western Greenland using a remotely controlled watercraft

    M. Tedesco


    Full Text Available Supraglacial lakes form from meltwater on the Greenland ice sheet in topographic depressions on the surface, affecting both surface and sub-glacial processes. As the reflectance in the visible and near-infrared regions of a column of water is modulated by its height, retrieval techniques using spaceborne remote sensing data (e.g. Landsat, MODIS have been proposed in the literature for the detection of lakes and estimation of their volume. These techniques require basic assumptions on the spectral properties of the water as well as the bottom of the lake, among other things. In this study, we report results obtained from the analysis of concurrent in-situ multi-spectral and depth measurements collected over a supraglacial lake during early July 2010 in West Greenland (Lake Olivia, 69°36'35" N, 49°29'40" W and aim to assess some of the underlying hypotheses in remote sensing based bathymetric approaches. In particular, we focus our attention on the analysis of the lake bottom albedo and of the water attenuation coefficient. The analysis of in-situ data (collected by means of a remotely controlled boat equipped with a GPS, a sonar and a spectrometer highlights the exponential trend of the water-leaving reflectance with lake depth. The values of the attenuation factor obtained from in-situ data are compared with those computed using approaches proposed in the literature. Also, the values of the lake bottom albedo from in-situ measurements are compared with those obtained from the analysis of reflectance of shallow waters. Finally, we quantify the error between in-situ measured and satellite-estimated lake depth values for the lake under study.

  17. Extraction of palaeochannei information from remote sensing imagery in the east of Chaohu Lake, China

    Xinyuan WANG; Zhenya GUO; Li WU; Cheng ZHU; Hui HE


    Palaeochannels are deposits of unconsolidated sediments or semi-consolidated sedimentary rocks deposited in ancient,currently inactive fiver and stream channel systems.It is distinct from the overbank deposits of currently active river channels,including ephemeral water courses which do not regularly flow.We have introduced a spectral characteristics-based palaeochannel information extraction model from SPOT-5 imagery with special time phase,which has been built by virtue of an analysis of remote sensing mechanism and spectral characteristics of the palaeochannel,combined with its distinction from the spatial distribution and spectral features of currently active river channels,also with the establishment of remote sensing judging features of the palaeochannel in remote sensing image.This model follows the process of supervised classification → farmland masking and primary component analysis → underground palaeochannel information extraction → information combination → palaeochannel system image.The Zhegao River Valley in the east of Chaohu Lake was selected as a study area,and SPOT-5 imagery was used as a source of data.The result was satisfactory when this method has been successfully applied to extract the palaeochannel information,which can provide good reference for regional remote sensing archeology and neotectonic research.However,the applicability of this method needs to be tested further in other areas as the spatial characteristics and spectral response of palaeochannel might be different.

  18. Changes of glacial lakes and implications in Tian Shan, central Asia, based on remote sensing data from 1990 to 2010

    Wang, Xin; Ding, Yongjian; Liu, Shiyin; Jiang, Lianghong; Wu, Kunpeng; Jiang, Zongli; Guo, Wanqin


    Changes of glacial lakes and implications were assessed for the Tian Shan Mountains from 1990 to 2010, based on Landsat Thematic Mapper/Enhanced Thematic Mapper Plus images. The total area of glacial lakes has expanded greatly over the last 20 years, at an average rate of 0.69 ± 0.12 km2 a-1 or 0.8 ± 0.1% a-1. Eastern Tian Shan contributed nearly half that increase (≈0.34 ± 0.03 km2 a-1), followed by northern Tian Shan at 0.17 ± 0.03 km2 a-1. Both widespread climate warming and glacier shrinking led to glacial lake areal expansion, while small to medium (lakes responded most sensitively to glacier retreat. The closer the hydrologic connection of lakes to glaciers, the greater the areal expansion rate. An average ≈0.007 ± 0.002 Gt a-1 of glacier meltwater has been temporarily held in lakes over the past two decades. The increasing quantity of melt available for lake formation and growth may simultaneously increase the frequency and damage of glacial lake outburst floods or debris flows in this region. Sixty potentially dangerous glacial lakes are identified, among which 12 have an outburst probability status of ‘high’, 25 ‘medium’ and 23 ‘low’.

  19. Real time remote monitoring and pre-warning system for Highway landslide in mountain area.

    Zhang, Yonghui; Li, Hongxu; Sheng, Qian; Wu, Kai; Chen, Guoliang


    The wire-pulling trigger displacement meter with precision of 1 mm and the grid pluviometer with precision of 0.1 mm are used to monitor the surface displacement and rainfall for Highway slope, and the measured data are transferred to the remote computer in real time by general packet radio service (GPRS) net of China telecom. The wire-pulling trigger displacement meter, grid pluviometer, data acquisition and transmission unit, and solar power supply device are integrated to form a comprehensive monitoring hardware system for Highway landslide in mountain area, which proven to be economical, energy-saving, automatic and high efficient. Meantime, based on the map and geographic information system (MAPGIS) platform, the software system is also developed for three dimensional (3D) geology modeling and visualization, data inquiring and drawing, stability calculation, displacement forecasting, and real time pre-warning. Moreover, the pre-warning methods based on monitoring displacement and rainfall are discussed. The monitoring and forecasting system for Highway landslide has been successfully applied in engineering practice to provide security for Highway transportation and construction and reduce environment disruption. Copyright © 2011 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

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

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


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

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

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


    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.

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

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


    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.

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

    Wenbin Zhu


    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

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

    Haeberli, Wilfried; Schaub, Yvonne; Huggel, Christian


    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

  5. A hundred year record of anthropogenic influences on the sedimentary geochemistry from Lake Sayram, Tianshan Mountains in northwestern China

    Wu, J.; Shen, B.


    Northwestern China has many arid inland lakes and wetlands, and it is characterized with climate variability and human impact. Lake Sayram is a deep, closed lake in the Tianshan Mountains of northwest China. In this study, we explore the trajectory of recent climate and environmental change using a 30-cm sediment record obtained from the center of Lake Sayram. With 210Pb and 137Cs dating and organic-inorganic geochemical methods, including element content, carbonate content, δ13C andδ18O of bulk carbonate, source-specific biomarkers and polycyclic aromatic hydrocarbons (PAHs), we reconstruct regional environmental change over the past about 100 yrs. High evaporation modifies δ13C andδ18O of the dissolved inorganic carbon in lake water and may be responsible for the covariance between δ13C andδ18O of bulk carbonate. Alkenone unsaturation indices are associated with climatic change, and the PAHs and metal contents reflect the impacts of human activities. Constrained cluster analysis of the multi-proxy indices was used to partition sediment deposition into three periods. Prior to 1960, the climate was dryer with high evaporation, and lake water had higher salinity. The vertical distributions of PAHs had little changed and low molecular weight PAHs were dominated PAHs. In this period, there existed one obvious drier climatic event at about 1920s with the sediment record of aeolian dust transport. From the 1960s to 1990s, high molecular weight PAHs and heavy metal delivery to sediments increased slowly, associated with relatively weak economic development in Xinjiang region. Thereafter, contamination by heavy metals increased markedly, especially after the 1990s, a sharp increase in PAHs level and individuals was observed too. The results clearly demonstrate that the environmental change in Lake Sayram before the 1960s strongly depended on the natural discharge, whereas at later stages, it was significantly influenced by human activities.

  6. Mountaineering



    Most young people enjoy some forms of physical activities.It may be walking,cycling or swimming,or in wither,skating or skiing.It may be a game of some kind,football,hockey(曲棍球),golf,or tennis.Perhaps it may be mountaineering.

  7. Remote sensing of landscape-level ecological attributes at Ray Roberts Lake in north Texas

    Smith, David P.

    Biological diversity is a key component in assessing ecosystem health. Alteration, degradation and loss of habitat due to human influence is currently the primary stressor resulting in decreases in diversity. Reliable assessment of large areas in terms of biological integrity are needed for conservation and preservation efforts. Remotely sensed data provide an integrated view of reflected electromagnetic energy over large areas of the earth. These energy patterns provide unique spectral signatures which can be correlated to land cover and habitat. This research sought relationships between traditional ecological measures and information gathered from satellite digital imagery. Reliable interpretation of earth surface characteristics relies largely on accurate rectification to a map projection and subsequent thematic classification. Use of the Global Positioning System (GPS) for rectification was superior than digitizing topographical maps. Differentially corrected GPS locations provided optimum rectification with SPOT satellite imagery while marginally better rectifications were obtained for Landsat MSS imagery using uncorrected GPS positions. SPOT imagery provided more accurate land cover classifications than did MSS. Detection of temporal land cover change using MSS imagery was hampered by confusion among intermediate successional classes. Confusion between upland and bottomland forest classes occurred with both SPOT and MSS. Landscape analyses using thematic maps produced from the previously discussed endeavors suggested that terrestrial habitat in the Ray Roberts Lake area became more fragmented and complex in shape. Habitat patches became smaller but more numerous. Forested areas were most affected and conservation efforts should focus on management strategies that promote vegetation succession and forest maturation. Remotely sensed SPOT data were successfully used to predict tree basal area. There were no significant relationships found with other in situ

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

    M. Mergili


    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.

  9. Developing a Near-Continuous Estimation of Volumetric Fluctuations in Tropical Lakes and Reservoirs Using Satellite Remote Sensing

    Keys, T.; Scott, D.


    Lakes and reservoirs play an integral role in water resources management by storing large quantities of water commonly used for irrigation, hydroelectric power, water supply, and flood mitigation. Knowing the exact quantity of stored water and necessary water for each of these usages is a critical component of sustainable water resources management. However, limited amounts of hydrologic data in developing nations, most of which are located in the tropics, hinders the accurate monitoring of water storage and allocation. Recent improvements in remote sensing have greatly enhanced the ability to calculate volumetric fluctuations of lakes and reservoirs at given points through time but are limited by temporal resolution as well as the computational time required for image processing. This study utilizes the newly developed MODISTools package for the programming language R in conjunction with satellite altimetry from three different altimetry databases to estimate lake and reservoir volumes at eight day intervals over a 15 year period. The study specifically examines three large lakes and reservoirs: Balbina Reservoir in the Amazon River Basin, Lake Tana in the Nile River Basin, and Tonle Sap Lake in the Mekong River Basin. Altimetry-based water level estimations are validated by in situ water level data from monitoring stations while surface area estimations are validated by Sound Navigation and Ranging (SONAR) generated bathymetric maps with corresponding stage-area relationships. Preliminary results indicate that both remotely sensed water levels and surface areas agree well with in situ measurements, supporting the appropriateness of this methodology.

  10. Multi-sensor time series of remote sensing data indicate rapid warming trend for lakes in California and Nevada

    Schneider, P.; Hook, S. J.; Radocinski, R. R.; Corlett, G. K.; Hulley, G. C.; Schladow, S. G.; Steissberg, T. E.


    The temperature of large lakes is a potential indicator of climate change. However, its usefulness is limited by the paucity of in situ measurements and lack of long-term data records. Thermal infrared (TIR) satellite imagery can be used to obtain frequent and accurate remote observations of lake surface temperatures. The archive of TIR imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS), the series of Along-Track Scanning Radiometers (ATSR/ATSR-2/AATSR) sensors, as well as from the series of Advanced Very High Resolution Radiometers (AVHRR), now spans nearly three decades and together these data sets can provide continuous time series of global lake surface temperatures. As part of an ongoing project involving the construction of 30-year time series of lake temperatures for 164 large lakes worldwide, we present the results of a case study for six lakes in California and Nevada. Seventeen years of data from the ATSR series was processed in combination with nine years of MODIS data in order to obtain time series of lake skin temperature. The accuracy of the skin temperature retrievals was tested against automated in situ measurements from buoys at the Lake Tahoe test site. The results indicate that nighttime skin temperatures can be estimated with mean errors as low as 0.2 °C. An analysis of average summer lake temperatures retrieved from the ATSR sensors shows that the six case study sites have exhibited average warming trends of 0.11 ± 0.026 °C yr-1 (p < 0.002) since 1992. The magnitude of the trend is confirmed by the shorter time series of MODIS data as well as by in situ measurements at Lake Tahoe. A comparison with air temperature observations suggests that the lake surface is warming more rapidly than the surface air temperature.

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

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


    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.

  12. Comparison of Atmospheric Parameters Derived from In-Situ and Hyper-/Multispectral Remote Sensing Data of Beautiful Bavarian Lakes

    Riedel, S.; Gege, P.; Schneider, M.; Pfug, B.; Oppelt, N.


    Atmospheric correction is a critical step and can be a limiting factor in the extraction of aquatic ecosystem parameters from remote sensing data of coastal and lake waters. Atmospheric correction models commonly in use for open ocean water and land surfaces can lead to large errors when applied to hyperspectral images taken from satellite or aircraft. The main problems arise from uncertainties in aerosol parameters and neglecting the adjacency effect, which originates from multiple scattering of upwelling radiance from the surrounding land. To better understand the challenges for developing an atmospheric correction model suitable for lakes, we compare atmospheric parameters derived from Sentinel- 2A and airborne hyperspectral data (HySpex) of two Bavarian lakes (Klostersee, Lake Starnberg) with in-situ measurements performed with RAMSES and Ibsen spectrometer systems and a Microtops sun photometer.

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

    Anderson, Lesleigh


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

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

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


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

  15. Remote Sensing supports EULAKES project for mapping submerged macrophytes in Lake Garda

    Matta, Erica; Bresciani, Mariano; Giardino, Claudia; Bolpagni, Rossano; Pellegrini, Giovanna; Braga, Federica


    Lake bottoms have an important role in the aquatic ecosystem: bathymetry and morphology may affect the hydrodynamic processes in coastal waters, while the presence of aquatic macrophytes helps to preserve the ecology. Within the context of macrophyte monitoring programs, technical advances in remote sensing with higher spatial and spectral resolutions provide opportunities for big scale ecological studies, with the possibility to assess a multitemporal analysis. One of the objectives of the EULAKES project has been to map aquatic vegetation cover inside the Garda Lake from hyperspectral MIVIS (Multispectral Infrared and Visible Imaging Spectrometer) aerial images thanks to the application of a bio-optical model inversion technique (BOMBER: Bio-Optical Model Based tool for Estimating water quality and bottom properties from Remote sensing images). MIVIS images, with a spectral resolution of 102 bands, working between 430 and 1270 nm, were previously corrected for atmospheric, adjacency and glint effects before being processed with the BOMBER tool. One complete MIVIS overflight (12 runs) acquired on June 27th 2011, allowed the retrieval of a macrophyte presence map all around the first 7m deep coastal belt, with a validation error of about 10%, resulting from 89 in situ measures performed during images acquisition. A relevant spatial distribution could be observed, with higher aquatic plants concentration in the Southern part of the lake. A further local cover distribution map localized on the Sirmione Peninsula was integrated with previous results to perform a temporal analysis of macrophyte colonization patterns along this reduced littoral zone for the last 14 years (acquisitions on September 1997, July 2005 and July 2010). Considerable modifications in terms of macrophyte structural complexity and colonized areas were detectable: a drastic reduction of well-established dense communities (more than 70% of cover) and increasing of un-colonized areas were followed by

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

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


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

  17. SOLS: A lake database to monitor in the Near Real Time water level and storage variations from remote sensing data

    Crétaux, J.-F.; Jelinski, W.; Calmant, S.; Kouraev, A.; Vuglinski, V.; Bergé-Nguyen, M.; Gennero, M.-C.; Nino, F.; Abarca Del Rio, R.; Cazenave, A.; Maisongrande, P.


    An accurate and continuous monitoring of lakes and inland seas is available since 1993 thanks to the satellite altimetry missions (Topex-Poseidon, GFO, ERS-2, Jason-1, Jason-2 and Envisat). Global data processing of these satellites provides temporal and spatial time series of lakes surface height with a decimetre precision on the whole Earth. The response of water level to regional hydrology is particularly marked for lakes and inland seas in semi-arid regions. A lake data centre is under development at by LEGOS (Laboratoire d'Etude en Géophysique et Océanographie Spatiale) in Toulouse, in coordination with the HYDROLARE project (Headed by SHI: State Hydrological Institute of the Russian Academy of Science). It already provides level variations for about 150 lakes and reservoirs, freely available on the web site (HYDROWEB:, and surface-volume variations of about 50 big lakes are also calculated through a combination of various satellite images (Modis, Asar, Landsat, Cbers) and radar altimetry. The final objective is to achieve in 2011 a fully operating data centre based on remote sensing technique and controlled by the in situ infrastructure for the Global Terrestrial Network for Lakes (GTN-L) under the supervision of WMO (World Meteorological Organization) and GCOS (Global Climate Observing System).


    Khulermaa B. Kuular


    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.

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

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


    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

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

    Dariusz Ficek


    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.

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

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


    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).

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

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


    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.

  3. Aquatic molluscs in high mountain lakes of the Eastern Alps (Austria): Species-environment relationships and specific colonization behaviour

    STURM Robert


    Mountain lakes represent essential stages for aquatic species on their way colonizing habitats of more elevated regions.Despite extensive biological and chemical study,only little has been reported about the species number and density of freshwater molluscs in these waters.The article presented here elucidates the dispersal of aquatic gastropods and bivalves in 12 mountain lakes that are commonly situated in the Eastern Alps,Austria.Molluscs were recorded at 120 sample points,where a total of 13 species (8 gastropods and 5 bivalves) could be determined.Species distribution data as well as results from contemporarily conducted physico-chemical factor recording were subject to weighted average analysis.In addition,a global marginality coefficient indicating the particularity of a habitat inhabited by a focal species as well as a global tolerance coefficient expressing the width of a niche occupied by this species were computed.Species-environment relationships exhibited that species number and specific density decrease with increasing geographic altitude,declining water temperature,and decreasing amount of submerged vegetation.Whilst waters of the montane altitude level are partly charcterized by high number of mollusc species (>10),lakes of the subalpine altitude level commonly bear 1 or 2 species with <<1 ind./m2.As proposed by the results of statistics,9 of the 13 mollusc species are characterized by a pronounced behaviour as specialists with respect to most environmental factors.The four remaining species,Pisidium casertanum,Galba truncatula,Radix labiata,and Radix balthica,act as generalists which increases their pioneering role in the long-term occupation of the Central-alpine region.

  4. Acidification and recovery at mountain lakes in Central Alps assessed by the MAGIC model

    Michela ROGORA


    Full Text Available The dynamic model MAGIC was calibrated and applied to 84 lakes in Central Alps to predict the response of water chemistry to different scenarios of atmospheric deposition of S and N compounds. Selected lakes were representative of a wide range of chemical characteristics and of sensitivity to acidification. The most sensitive lakes have already shown in the latest years signs of recovery in terms of pH and ANC. The model well captured the main trends in lake chemical data. According to the model forecast, recovery at sensitive lakes will continue in the next decades under the hypothesis of a further decrease of acidic input from the atmosphere. Results clearly demonstrated the benefits of achieving the emission reductions in both S and N compounds agreed under the Gothenburg Protocol. Nevertheless, besides the achieved reduction of SO4 2- deposition from the peak levels of the 80s, also N deposition should be reduced in the near future to protect alpine lakes from further acidification. The condition of lake catchments with regard to N saturation will probably be the dominant factor driving recovery extent. Beside atmospheric deposition, other factors proved to be important in determining long-term changes in surface water chemistry. Climate warming in particular affects weathering processes in lake catchments and dynamics of the N cycle. Including other factors specific to the alpine area, such as dust deposition and climate change, may improve the fit of experimental data by the model and the reliability of model forecast.

  5. Strong differences in the clonal variation of two Daphnia species from mountain lakes affected by overwintering strategy

    Mergeay Joachim


    Full Text Available Abstract Background The population structure of cyclical parthenogens such as water fleas is strongly influenced by the frequency of alternations between sexual and asexual (parthenogenetic reproduction, which may differ among populations and species. We studied genetic variation within six populations of two closely related species of water fleas of the genus Daphnia (Crustacea, Cladocera. D. galeata and D. longispina both occur in lakes in the Tatra Mountains (Central Europe, but their populations show distinct life history strategies in that region. In three studied lakes inhabited by D. galeata, daphnids overwinter under the ice as adult females. In contrast, in lakes inhabited by D. longispina, populations apparently disappear from the water column and overwinter as dormant eggs in lake sediments. We investigated to what extent these different strategies lead to differences in the clonal composition of late summer populations. Results Analysis of genetic variation at nine microsatellite loci revealed that clonal richness (expressed as the proportion of different multilocus genotypes, MLGs, in the whole analysed sample consistently differed between the two studied species. In the three D. longispina populations, very high clonal richness was found (MLG/N ranging from 0.97 to 1.00, whereas in D. galeata it was much lower (0.05 to 0.50. The dominant MLGs in all D. galeata populations were heterozygous at five or more loci, suggesting that such individuals all represented the same clonal lineages rather than insufficiently resolved groups of different clones. Conclusions The low clonal diversities and significant deviations from Hardy-Weinberg equilibrium in D. galeata populations were likely a consequence of strong clonal erosion over extended periods of time (several years or even decades and the limited influence of sexual reproduction. Our data reveal that populations of closely related Daphnia species living in relatively similar habitats

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

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


    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.

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

    S. I. Khan


    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

  8. Background continental atmospheric deposition from a remote alpine site in the Canadian Southern Rocky Mountains

    Wasiuta, V. L.; Norman, A. L.; Lafreniere, M. J.; Hastings, M. G.


    Precipitation from the remote alpine Haig Valley in the Canadian Southern Rocky Mountains provides a useful baseline for background atmospheric sulphur (S) and nitrogen (N) deposition. Major controls on deposition were evaluated using seasonal glacier snowpack, reflecting atmospheric deposition from Sept. 2008 to April 2009, and Sept. 2009 to May 2010, along with June 28-August 22 2010, bulk summer precipitation. A narrow range in δ34S-SO42- values in bulk summer precipitation (6.1-8.7‰, n=12) with uniform S loads, at varied elevations, across the Haig Valley indicate atmospheric sulphate (SO42-) was well-mixed prior to deposition and dominantly from long range transport. Uniform ammonium (NH4+) loads also indicated well mixed dominantly distant sources for this N aerosol. Snowpack loads varied closely with snow water equivalent, which was orographically controlled. Deposition patterns for nitrate (NO3-) and nitrite (NO2-) along with δ15N-NO3- and δ18O-NO3- from summer bulk precipitation (with elevation in the SE facing Haig Valley and opposing NNW facing Robertson Valley), showed δ18O-NO3- values and [NO2-] to be effective tracers of regional (within 24 hours of atmospheric transport) NOx combustion emissions. Distant emissions (> 1 day transport), with high δ18O-NO3 values consistent with NOx oxidation dominantly by ozone, were associated with relatively high δ15N-NO3- values. In contrast, lower δ18O-NO3- values that reflect a higher proportion of NOx oxidation by atmospheric H2O and O2 and are consistent with an increased proportion of regional combustion emissions, were accompanied by lower δ15N-NO3- values. Combined analytical results from snowpack and summer precipitation showed a negative covariance of δ18O-NO3- values with [NO3-]. Summer precipitation formed the high [NO3-], low δ18O-NO3- segment of a trend with snowpack at the other end with low concentrations and high δ18O-NO3-values. [NO2-] and δ18O-NO3-values also negatively covaried

  9. Response of alpine lakes and soils to changes in acid deposition: the MAGIC model applied to the Tatra Mountain region, Slovakia-Poland

    Josef VESELÝ


    Full Text Available A dynamic process-based model of surface water acidification, MAGIC, was applied to 31 representative alpine lakes in the Tatra Mountains (~50% of all alpine lakes >0.3 ha in the lake-district. The model was calibrated to observed lake chemistry for the period 1980-2002. Surface water and soil chemistry were reconstructed from 1860 to 2002, given estimates of historical acid deposition, and forecast to 2020 based on the reduction in sulphur and nitrogen emissions presupposed by the Gothenburg Protocol. In the 1860s, all lakes were buffered by the carbonate system and only ~6% of lakes had acid neutralising capacity (ANC 50% of the SAA change in sensitive lakes with intermediate weathering rates and little soils (low BC exchangeable capacity and elevated terrestrial export of nitrate and (3 by parallel changes in concentrations of protons and aluminium (each ~20% of the SAA change in extremely sensitive lakes, with the lowest weathering rates and soil base saturation. The full implementation of the Gothenburg Protocol will not be sufficient to allow recovery of the latter group of lakes, which will remain acidified after 2020.

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

    Eleonora Semakova


    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.

  11. Mercury in Tadpoles Collected from Remote Alpine Sites in the Southern Sierra Nevada Mountains, California, USA

    Amphibians in alpine wetlands of the Sierra Nevada mountains comprise key components of an aquatic-terrestrial food chain, and mercury contamination is a concern because concentrations in fish from this regin exceed thresholds of risk to piscivorous wildlife. Total mercury conc...

  12. Combining remote sensing and GIS climate modelling to estimate daily forest evapotranspiration in a Mediterranean mountain area

    J. Cristóbal


    Full Text Available Evapotranspiration monitoring allows us to assess the environmental stress on forest and agricultural ecosystems. Nowadays, Remote Sensing and Geographical Information Systems (GIS are the main techniques used for calculating evapotranspiration at catchment and regional scales. In this study we present a methodology, based on the energy balance equation (B-method, that combines remote sensing imagery with GIS climate modelling to estimate daily evapotranspiration (ETd for several dates between 2003 and 2005. The three main variables needed to compute ETd were obtained as follows: (i Land surface temperature by means of the Landsat-5 TM and Landsat-7 ETM+ thermal band, (ii air temperature by means of multiple regression analysis and spatial interpolation from meteorological ground stations data at satellite pass, and (iii net radiation by means of the radiative balance. We calculated ETd using remote sensing data at different spatial and temporal scales (TERRA/AQUA MODIS and Landsat-5 TM/Landsat-7 ETM+ and combining three different approaches to calculate the B parameter. We then compared these estimates with sap flow measurements from a Scots pine (Pinus sylvestris L. stand in a Mediterranean mountain area. This procedure allowed us to better understand the limitations of ETd modelling and how it needs to be improved, especially in heterogeneous forest areas. The method using Landsat data resulted in a good agreement, with a mean RMSE value of about 0.6 mm day−1 and an estimation error of ±30%. The poor agreement obtained using MODIS data reveals that ETd retrieval from coarse resolution remote sensing data is troublesome in these heterogeneous areas, and therefore further research is necessary on this issue.

  13. The Provision of Sexual and Reproductive Health Education to Children in a Remote Mountainous Commune in Rural Vietnam: An Exploratory Study of Parents' Views

    Ha, Tran Thi Thu; Fisher, Jane R. W.


    The purpose of this study was to explore the expectations of parents in a remote mountainous commune in Vietnam about sexual and reproductive health (SRH) education for their children. Separate in-depth interviews were conducted with 34 parents of eight-year-old children and key informants including a principal, a teacher and staff of the Youth…

  14. The Provision of Sexual and Reproductive Health Education to Children in a Remote Mountainous Commune in Rural Vietnam: An Exploratory Study of Parents' Views

    Ha, Tran Thi Thu; Fisher, Jane R. W.


    The purpose of this study was to explore the expectations of parents in a remote mountainous commune in Vietnam about sexual and reproductive health (SRH) education for their children. Separate in-depth interviews were conducted with 34 parents of eight-year-old children and key informants including a principal, a teacher and staff of the Youth…

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

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


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

  16. Analysis of Remote Sensing Images of Ground Ruptures Resulting from the Kunlun Mountain Pass Earthquake in 2001

    SHAN Xinjian; LI Jianhua; MA Chao; LIU Jiahang


    On November 14, 2001, an earthquake measuring a magnitude of 8.1 occurred to the west of the Kunlun Mountain Pass which is near the border between Xinjiang and Qinghai of China. Since its epicenter is located in an area at an elevation of 4900 m where the environment is extremely adverse, field investigation to this event seems very difficult.We have performed interpretation and analysis of the satellite images of ETM, SPOT, Ikonos, and ERS-1/2SAR to reveal the spatial distribution and deformation features of surface ruptures caused by this large earthquake. Our results show that the rupture zone on the ground is 426 km long, and strikes N90-110°E with evident left-lateral thrusting. In spatial extension, it has two distinct sections. One extends from the Bukadaban peak to the Kunlun Mountain Pass, with a total length of 350 km, and trending N95-110°E. Its fracture plane is almost vertical, with clear linear rupture traces and a single structure, and the maximum left-lateral offset is 7.8 m. This section is the main rupture zone caused by the earthquake,which is a re-fracturing along an old fault. The other is the section from Kushuihuan to the Taiyang Lake. It is 26 km long,trending N90-105°E, with the maximum strike-slip displacement being 3 m, and is a newly-generated seismic rupture. In a 50 km-long section between the Taiyang Lake and the Bukadaban peak, no rupture is found on the ground. The eastern and western rupture zones may have resulted from two earthquakes. The macroscopic epicenter is situated at 65 km east of the Hoh Sai Lake. The largest coseismic horizontal offset in the macroscopic epicenter ranges from 7 m to 8 m. Based on the dislocation partition of the whole rupture zone, it is suggested that this rupture zone has experienced a process of many times of intensification and fluctuation, exhibiting a remarkable feature of segmentation.

  17. Revised volcanic history of the San Juan, Uncompahgre, Silverton, and Lake City calderas in the western San Juan Mountains, Colorado

    Lipman, Peter W.; Steven, Thomas A.; Luedke, Robert G.; Burbank, Wilbur


    The sequence of mid-Cenozoic volcanic events in the western San Juan Mountains is closely analogous to that elsewhere in the San Juan volcanic field. The Lake Fork, Picayune, and San Juan Formations were erupted from a cluster of central volcanoes from 35 to 30 m.y. ago, when dominant activity shifted to more silicic ash-flow eruptions with accompanying caldera collapses. The Uncompahgre and San Juan calderas, each about 20 km across, formed mainly from eruption of the 28-m.y.-old Sapinero Mesa Tuff. Collapse occurred concurrently with eruption, and intracaldera tuffs accumulated to a thickness of more than 700 m. Both calderas were resurgently domed together; the northeast-trending Eureka graben formed along the distended crest of that dome. The Uncompahgre caldera was then flooded by several 27- to 28-m.y.-old ash-flow sheets from easterly sources, and also by one apparently erupted from the Silverton caldera nested within the older San Juan caldera. The Lake City caldera, located within the older Uncompahgre caldera, formed about 22.5 m.y. ago in response to eruption of the Sunshine Peak Tuff.

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

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


    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

  19. 遥感和GIS在冰湖溃决洪水中的应用研究%An Application Research of Remote Sensing and GISi n Glacial Lake Outburst Flood Hazards



    近年来随着全球气候变暖和冰川退缩,以及人类在高海拔地区活动的增多,冰湖溃决洪水灾害呈增加趋势。由于遥感和GIS技术的众多优势,使其在冰湖溃决洪水研究方面得到广泛应用。首先对冰湖溃决洪水及其研究做简单介绍,然后从冰川、冰湖空间数据获取,冰湖溃决评价指标获取,冰湖溃决洪水模拟和DEM的建立及应用4个方面对遥感和GIS在冰湖溃决洪水研究中的应用进行综述,最后指出,目前遥感和GIS在冰湖溃决洪水应用中的不足,为进一步研究和应用指明了方向。%Abstrca t:With the atmospheric warming and glacier retreating in recent years, GLOF ( Glacial Lake Outburst Flood) hazards are in-creasingly threatening people ( s life and property.Researches on GLOFs have made great progress.Because of many advantages of Re-mote Sensing and GIS, they are used widely in GLOFs which situate in inaccessible high-mountain regions.At first, this paper sim-ply introduces GLOF hazards and researches on it .Then it provides an overview about the application of Remote sensing and GIS in GLOF hazards from mapping of glacier and glacial lake, Acquisition of candidate indexes for glacial lake risk assessment, Glacial lake outburst modeling as well as generation and use of remote sensing-derived DEMs.Finally, the paper outlines insufficiency of applica-tion of Remote Sensing and GIS in GLOF hazards, which help us focus on researches about Remote Sensing and GIS for better using them in GLOF hazards.

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

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


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

  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

    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)


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

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


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

  3. Forest Condition Monitoring Using Very-High-Resolution Satellite Imagery in a Remote Mountain Watershed in Nepal

    Kabir Uddin


    Full Text Available Satellite imagery has proven extremely useful for repetitive timeline-based data collection, because it offers a synoptic view and enables fast processing of large quantities of data. The changes in tree crown number and land cover in a very remote watershed (area 1305 ha in Nepal were analyzed using a QuickBird image from 2006 and an IKONOS image from 2011. A geographic object-based image analysis (GEOBIA was carried out using the region-growing technique for tree crown detection, delineation, and change assessment, and a multiresolution technique was used for land cover mapping and change analysis. The coefficient of determination for tree crown detection and delineation was 0.97 for QuickBird and 0.99 for IKONOS, calculated using a line-intercept transect method with 10 randomly selected windows (1×1 ha. The number of tree crowns decreased from 47,121 in 2006 to 41,689 in 2011, a loss of approximately 90 trees per month on average; the area of needle-leaved forest was reduced by 140 ha (23% over the same period. Analysis of widely available very-high-resolution satellite images using GEOBIA techniques offers a cost-effective method for detecting changes in tree crown number and land cover in remote mountain valleys; the results provide the information needed to support improved local-level planning and forest management in such areas.

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

    Mulders, M.A.


    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 v

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

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


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

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

    Li, Gang; Lin, Hui


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

  7. Remote sensing evaluation of the regional chemistry and element dispersion of porphyry copper deposits in the Silver Bell Mountains, Arizona

    Jaramillo-Nieves, Lorna G.

    Porphyry copper deposits in southeastern Arizona belong to a cluster of 38 mineralized centers covering a region extending from northern Mexico to western New Mexico and southern Arizona. Presently, some of these deposits are being actively mined and the rest are prospects or abandoned mining sites. As a result of the large number of porphyry copper deposits in this region, research on the interaction between mineralized centers and the environment is important; in particular, the dispersion characteristics of acid-generating metal-enriched materials at the shallow alluvial margins of these centers. The present research uses remote sensing techniques, groundwater chemistry, trace element, and mineralogical analysis to characterize dispersion chemistry surrounding porphyry copper deposits in the Silver Bell Mountains. Hyperspectral imagery obtained by the Airborne Visible/Infrared Spectrometer and HyMap are used to map supergene minerals by analyzing their spectral profiles in the visible and short wave infrared regions of the electromagnetic spectrum. Reflectance profiles are characteristic of each mineral and shifts in absorption features within one mineral are a result of differences in cation content. Image reflectance profiles are compared with stream sediment mineralogy and reflectance spectral profiles to better outline concentrations of Fe, S, K, Na, Ca, Mg, Cu, and Al. In addition, groundwater modeling in the Silver Bell Mountains is considered for various flow paths within shallow aquifers in the region and compared to actual groundwater chemistry and surface lithology. The Silver Bell Mountains serve as a case study for element mobility and concentration distribution in other areas where undisturbed deposits, historic and present-day excavation activity occurs, where semi-arid climate and a deep vadose zone are variables that influence element mobility and concentration. Results obtained from hyperspectral image processing indicate the possible enrichment

  8. Bacterial ‘cosmopolitanism’ and importance of local environmental factors for community composition in remote high-altitude lakes



    SUMMARY In October 2004, plankton samples were collected from six permanent lakes located between 4960 and 5440 m a.s.l. in the Mount Everest region (Nepal) to assess how spatial and local environmental factors affect natural bacterial community composition. Fingerprinting analysis of the bacterial 16S rRNA gene fragment was done by denaturing gradient gel electrophoresis (DGGE). The number of DGGE bands (range: 12–23) was not correlated with lake area or remoteness, but there was a strong negative correlation with the ratio of catchment to lake area (r = −0.826, P 98 to 100%) in partial 16S rRNA gene sequence to those reported from other alpine lakes and glaciers around the world, suggesting the presence of ‘cosmopolitan’ bacteria. An analysis based on dissimilarity matrices and the Mantel test revealed the existence of dissimilarities in bacterial community composition related to geographical distance over a small spatial scale (aquatic realm, but taxon sorting by local environmental constraints is important. PMID:20543908

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

    Vannah, Benjamin; Chang, Ni-Bin


    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.

  10. The geomorphology of Patagonian ice dammed lake basins: Insights from remote sensing of a modern lake and reconstruction of a Late Quaternary lake drainage event

    Thorndycraft, Varyl


    The geomorphology of ice dammed lake basins can be complex due to geomorphic responses to multiple base level changes from repeated filling and emptying, as well as the potential for catastrophic drainage events. Refining landscape models of Quaternary ice dammed palaeolake systems has the potential to improve our understanding of glacier and meltwater dynamics during deglaciation phases. In this poster two case studies are presented to shed light on the range of geomorphic processes exhibited within ice dammed lake basins. Using Google Earth Pro and repeat LANDSAT imagery the geomorphology resulting from multiple base level changes of an ice dammed lake of the Viedma Glacier (Southern Patagonia Icefield) is presented. The LANDSAT imagery shows transgressive lake phases inundating already formed delta and terrace surfaces, whilst the high resolution Google Earth Pro images reveal a complex suite of incised terrace levels developed on the valley floor following lake drainage events. Secondly, the impact of catastrophic drainage of the Late Pleistocene Palaeolake Cochrane (Northern Patagonia Icefield) is investigated through geomorphological mapping. Here an outburst flood and rapid lowering of the lake has led to large scale eddy scouring of glacio-lacustrine sediments, with scarp slopes of ca. 30-40 m in height, and the formation of boulder bars during the final stages of lake fall. The implications of the mapping for interpretations of Late Quaternary palaeolake sediment-landform assemblages and rates of landscape change are discussed.

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

    Cristina Pulido


    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

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

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


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

  13. Distribution and recent variations of supraglacial lakes on dendritic-type glaciers in the Khan Tengri-Tomur Mountains, Central Asia

    Q. Liu


    Full Text Available Supraglacial lakes are widely distributed on glaciers in the Tomur-Khan Tengri Tianshan Mountains, Central Asia. The existence and development of supraglacial lakes play an important role in the ice melting processes and also in the storage and release of glacial melt water. Here we mapped the supraglacial lakes of eight typical debris-covered dendritic-type glaciers around the Tomur-Khan Tengri peaks based on 9 Landsat TM/ETM+ images acquired in the summers of 1990 until 2011. With a lower area limit of 3600 m2 for a conservative identification of glacial lakes, we mapped 775 supraglacial lakes and 38 marginal glacial lakes in total. Our results indicate that supraglacial lakes (area > 3600 m2 in the study region never develop beyond an elevation of about 3850 m a.s.l., 800 m lower than the maximum upper boundary of debris cover (4650 m a.s.l.. The area-elevation distribution shows that lakes are predominantly occured close to the altitude of 3250 m a.s.l., where the clean ice simultaneously disappears. The majority of the supraglacial lakes are found on the Tomur Glacier and the South Inylchek Glacier, two strongly debris-covered dendritic-type glaciers in the region. As for the multi-year variation of lake area, the summer total and mean areas of supraglacial lakes show some variability from 1990 and 2005 but increased noticeably between 2005 and 2011. The mean area of the mapped lakes reached a maximum in 2010. We found that the area of supraglacial lakes is positively correlated to the total precipitation in summer (July to September but negatively correlated to the mean spring air temperature (April to June. Pre-summer air temperature fluctuations likely have a stronger impact on the different evolution processes of glacial drainage, evolving from unconnected to connected systems, which may lead to the drainage of larger supraglacial lakes and results in shrinkage of the total and mean lake area during the summer.

  14. A new remote hazard and risk assessment framework for glacial lakes in the Nepal Himalaya

    Rounce, David R.; McKinney, Daene C.; Lala, Jonathan M.; Alton C. Byers; Watson, C. Scott


    Glacial lake outburst floods (GLOFs) pose a significant threat to downstream communities and infrastructure due to their potential to rapidly unleash stored lake water. The most common triggers of these GLOFs are mass movement entering the lake and/or the self-destruction of the terminal moraine due to hydrostatic pressures or a buried ice core. This study initially uses previous qualitative and quantitative assessments to understand the hazards associated with eight glacial...

  15. A extract method of mountainous area settlement place information from GF-1 high resolution optical remote sensing image under semantic constraints

    Guo, H., II


    Spatial distribution information of mountainous area settlement place is of great significance to the earthquake emergency work because most of the key earthquake hazardous areas of china are located in the mountainous area. Remote sensing has the advantages of large coverage and low cost, it is an important way to obtain the spatial distribution information of mountainous area settlement place. At present, fully considering the geometric information, spectral information and texture information, most studies have applied object-oriented methods to extract settlement place information, In this article, semantic constraints is to be added on the basis of object-oriented methods. The experimental data is one scene remote sensing image of domestic high resolution satellite (simply as GF-1), with a resolution of 2 meters. The main processing consists of 3 steps, the first is pretreatment, including ortho rectification and image fusion, the second is Object oriented information extraction, including Image segmentation and information extraction, the last step is removing the error elements under semantic constraints, in order to formulate these semantic constraints, the distribution characteristics of mountainous area settlement place must be analyzed and the spatial logic relation between settlement place and other objects must be considered. The extraction accuracy calculation result shows that the extraction accuracy of object oriented method is 49% and rise up to 86% after the use of semantic constraints. As can be seen from the extraction accuracy, the extract method under semantic constraints can effectively improve the accuracy of mountainous area settlement place information extraction. The result shows that it is feasible to extract mountainous area settlement place information form GF-1 image, so the article proves that it has a certain practicality to use domestic high resolution optical remote sensing image in earthquake emergency preparedness.

  16. Change detection for Lake Burullus, Egypt using remote sensing and GIS approaches.

    Mohsen, A; Elshemy, M; Zeidan, B A


    Lake Burullus is the second largest natural coastal lake in Egypt. It has an economic importance for fish yield. However, several anthropogenic activities such as industrial, agriculture, and reclamation activities lead to a deterioration of its water quality and a decrease of the water body area of the lake. This study aims to detect the spatiotemporal changes of Lake Burullus in the period 1972-2015 using 12 Landsat {(1,3-MSS), (4,5-TM), and (7-ETM+)} imageries and water indices approach. To extract water feature from imageries, the Normalized Difference Water Index (NDWI) and the Water Ratio Index (WRI) were applied. The NDWI was applied to the MSS imageries. For other TM and ETM+ imageries, the WRI was applied. Obtained results show a significant decrease in the water area of the Lake Burullus, where it lost about (49%) of its surface area during the period from the year 1972 to the year 2015. A rapid decrease in the lake surface area was noticed through the period from 1972 to 1984. A prediction model was built depending on the calculated water area of the lake. Finally, the multi-temporal maps of the lake surface area are overlaid to produce a map for the changes of the lake surface area using Geographic Information System (GIS).

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

    Chachere, Catherine N.; Pu, Zhaoxia


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

  18. Turbidites as indicators of paleotopography, Upper Miocene Lake Pannon, Western Mecsek Mountains (Hungary)

    Sztanó Orsolya; Sebe Krisztina; Csillag Gábor; Magyar Imre


    The floor of Lake Pannon covering the Pannonian Basin in the Late Miocene had considerable relief, including both deep sub-basins, like the Drava Basin, and basement highs, like the Mecsek Mts, in close proximity. The several km thick lacustrine succession in the Drava Basin includes profundal marls, basin-center turbidites, overlain by shales of basin-margin slopes, coarsening-upward deltaic successions and alluvial deposits. Along the margin of the Mecsek Mts locally derived shoreface sands...

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

    Platt, Bradbury J.


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

  20. Combining remote sensing and GIS climate modelling to estimate daily forest evapotranspiration in a Mediterranean mountain area

    J. Cristóbal


    Full Text Available Evapotranspiration monitoring allows us to assess the environmental stress on forest and agricultural ecosystems. Nowadays, Remote Sensing and Geographical Information Systems (GIS are the main techniques used for calculating evapotranspiration at catchment and regional scales. In this study we present a methodology, based on the energy balance equation (B-method, that combines remote sensing imagery with GIS-based climate modelling to estimate daily evapotranspiration (ETd for several dates between 2003 and 2005. The three main variables needed to compute ETd were obtained as follows: (i Land surface temperature by means of the Landsat-5 TM and Landsat-7 ETM+ thermal band, (ii air temperature by means of multiple regression analysis and spatial interpolation from meteorological ground stations data at satellite pass, and (iii net radiation by means of the radiative balance. We calculated ETd using remote sensing data at different spatial and temporal scales (Landsat-7 ETM+, Landsat-5 TM and TERRA/AQUA MODIS, with a spatial resolution of 60, 120 and 1000 m, respectively and combining three different approaches to calculate the B parameter, which represents an average bulk conductance for the daily-integrated sensible heat flux. We then compared these estimates with sap flow measurements from a Scots pine (Pinus sylvestris L. stand in a Mediterranean mountain area. This procedure allowed us to better understand the limitations of ETd modelling and how it needs to be improved, especially in heterogeneous forest areas. The method using Landsat data resulted in a good agreement, R2 test of 0.89, with a mean RMSE value of about 0.6 mm day−1 and an estimation error of ±30 %. The poor agreement obtained using TERRA/AQUA MODIS, with a mean RMSE value of 1.8 and 2.4 mm day−1 and an estimation error of about ±57 and 50 %, respectively. This

  1. Identifying and Evaluating Possible Trigger Mechanisms for Glacial Lake Outburst Floods in the Hindu Kush Himalayas Using Remote Sensing Satellite Data

    Hess, T. G.; Haritashya, U. K.


    Glacierized basins in high-altitude and mountainous areas, such as the Himalayas, have seen an increase in the number of glacial lakes over the years as a result of a changing climate. As the meltwater becomes more prevalent, the runoff can accumulate in a depression left behind by the receding glacier and can be bound by the walls of frontal and lateral moraines. These moraines, however, often are comprised of loose, unconsolidated sediment and can prove to be unstable dam structures for proglacial lakes. The factor of instability associated with the moraines poses a serious threat for failure and severe flooding. If the moraines were to be breached by the lake water, a phenomenon known as a glacial lake outburst flood (GLOF) can occur, potentially putting lives and infrastructure in harm's way. Consequently, this study examines the likelihood of a GLOF occurrence by analyzing potential trigger mechanisms associated with three proglacial lakes in the Hindu Kush Himalayan region. Using ASTER satellite imagery, one lake from Nepal, India, and Bhutan have each been assessed for possible trigger mechanisms. Our results suggest that steep-sided moraines, rugged topography, unstable masses on the upper reaches of steep slopes, and smaller lakes perched high above can all be classified as possible trigger mechanisms for the areas of study. It is imperative to be able to successfully identify potential trigger mechanisms using satellite data so that further ground observations can be made and mitigation efforts can be incorporated where needed. As lakes continue to grow, so does the cause for concern for possible GLOFs. Glacial lake outburst floods are being studied more extensively now due to the greater number of glacial lakes in high-mountainous areas. It is vitally important to understand the dynamics of a GLOF, especially the potential trigger mechanisms associated with it.

  2. [Remote sensing based monitoring of vegetation dynamics and ecological restoration in Beijing mountainous area].

    Hu, Yong; Liu, Liang-yun; Jia, Jian-hua


    By using the Landsat images in 1979, 1988, 1999, 2005, and 2009, and the linear unmixed model at pixel scale, this paper analyzed the spatiotemporal variation of vegetation coverage in Beijing mountainous area. After detecting the areas of vegetation degradation or restoration, the impacts of elevation, slope, and soil type on vegetation restoration were studied. From 1979 to 1988, the vegetation coverage in the study area had no obvious change, but in the following 12 years, the vegetation coverage was seriously destroyed due to the fast development of social economy. Fortunately, many protective measures were taken since 2000, which improved the vegetation coverage to 72% in 2009, with an increment of 13% compared to the vegetation coverage in 1999. A significant correlation was observed between the variations of vegetation coverage and territorial features. The areas with poor soil or large slope were more easily suffered from degradation than other places, and the flat regions with low elevation were more affected by human activities.

  3. The use of remote sensing to quantify wetland loss in the Choke Mountain range, Upper Blue Nile basin, Ethiopia

    E. Teferi


    Full Text Available Wetlands provide multiple ecosystem services such as storing and regulating water flows and water quality, providing unique habitats to flora and fauna, and regulating micro-climatic conditions. Conversion of wetlands for agricultural use is a widespread practice in Ethiopia, particularly in the southwestern part where wetlands cover large areas. Although there are many studies on land cover and land use changes in this region, comprehensive studies on wetlands are still missing. Hence, extent and rate of wetland loss at regional scales is unknown. The objective of this paper is to quantify wetland dynamics and estimate wetland loss in the Choke Mountain range (area covering 17 443 km2 in the Upper Blue Nile basin, a key headwater region of the river Nile. Therefore, satellite remote sensing imagery of the period 1986–2005 were considered. To create images of surface reflectance that are radiometrically consistent, a combination of cross-calibration and atmospheric correction (Vogelman-DOS3 methods was used. A hybrid supervised/unsupervised classification approach was used to classify the images. Overall accuracies of 94.1% and 93.5% and Kappa Coefficients of 0.908 and 0.913 for the 1986 and 2005 imageries, respectively were obtained. The results showed that 607 km2 of seasonal wetland with low moisture and 22.4 km2 of open water are lost in the study area during the period 1986 to 2005. The current situation in the wetlands of Choke Mountain is characterized by further degradation which calls for wetland conservation and rehabilitation efforts through incorporating wetlands into watershed management plans.

  4. The use of remote sensing to quantify wetland loss in the Choke Mountain range, Upper Blue Nile basin, Ethiopia

    E. Teferi


    Full Text Available Wetlands provide multiple ecosystem services such as storing and regulating water flows and water quality, providing unique habitats to flora and fauna, and regulating micro-climatic conditions. Conversion of wetlands for agricultural use is a widespread practice in Ethiopia, particularly in the southwestern part where wetlands cover large areas. Although there are many studies on land cover and land use changes in this region, comprehensive studies on wetlands are still missing. Hence, extent and rate of wetland loss at regional scale is unknown. The objective of this paper is to quantify wetland dynamics and estimate wetland loss in the Choke Mountain range (area covering 17 443 km2 in the Upper Blue Nile basin, a key headwater region of the river Nile. Therefore, satellite remote sensing images of the period 1986–2005 were considered. To create images of surface reflectance that are radiometrically consistent, a combination of cross-calibration and atmospheric correction (Vogelman-DOS3 methods was used. A hybrid supervised/unsupervised classification approach was used to classify the images. Overall accuracies of 94.1% and 93.5% and Kappa Coefficients of 0.908 and 0.913 for the 1986 and 2005 imageries, respectively were obtained. The results showed that 607 km2 of seasonal wetland with low moisture and 22.4 km2 of open water are lost in the study area during the period 1986 to 2005. The current situation in the wetlands of Choke Mountain is characterized by further degradation which calls for wetland conservation and rehabilitation efforts through incorporating wetlands into watershed management plans.

  5. Monitoring of vegetation impact due to trampling on Cadillac Mountain summit using high spatial resolution remote sensing data sets.

    Kim, Min-Kook; Daigle, John J


    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 vegetation at the site level. Management implications are explored in terms of the spatial strategies used to decrease the impact of trampling on vegetation.

  6. Hydro-climatic Investigation of Lake Urmia Shrinkage using Remote Sensing

    Khazaei, B.; Khatami, S.; Rashidi, L.; Madani, K.


    Lake Urmia (LU) is a shallow endemic lake located in Northwest Iran. Once one of the largest saline lakes in the world, its water level has dramatically dropped by about 7 m since 1997. There has been a contested debate around the major cause(s) of the lake shrinkage and whether this has been due to climatic changes or anthropogenic interventions in the lake's basin. Using MODIS data, we estimate the changes in normalized difference vegetation index (NDVI) during the 2000-2015 period. NDVI represents the average quality of vegetation and vegetation coverage and used in this study as an indicator of agricultural drought. Comparison of NDVI with observed precipitation (P), temperature (T), and Lake water level (WL) shows that P and NDVI are significantly and positively correlated with similar trends of near-to-horizontal. Since a significant portion of green coverage represented by NDVI are agricultural lands, the negative correlation between NDVI and WL reflects the trade-off between the declining WL and agricultural development in the basin resulting in less water inflows. A very poor and negative correlation between T and WL could reflect the low contribution of evaporation to the lake's water level decline. However, the normal trend of T weakens the current argument by the local decision makers that the lake has been affected by extreme climatic change. Trend analysis suggests that P, T, and NDVI are in harmony with each other, indicating no extreme climatic regime in the basin. In light of the above, an ever-decreasing trend of WL during the past two decades cannot be simply explained by the hydro-climatology of the lake. Our findings highlight the need to putting more emphasis on understanding the anthropogenic effects of regional development, rather than blaming climatic changes, in the process of developing lake management and restoration plans.

  7. Integrated HS and ALS Remote Sensing Data Sources to Develop Green Corridors in Sopron Mountains

    János Tamás


    Full Text Available The green corridors are part of the European Union rural landscapes, but the regional increase in size of agricultural parcels had a significant effect on European land use in the 20th century. This effect radically reduced the coverage of natural forest. One ecological problem with the remaining forests is the partial missing of the network connecting the parts with ecological green corridors. Another economical problem is the verifiability for the payment system of agroforestry. Remote sensing methods are currently used to supervise monitoring the arable lands, plantations, natural reserve areas, as well as to help for the European Union payment system. Nowadays the airborne hyperspectral (HS and LiDAR (Light Detection And Ranging; ALS remote sensing technologies are becoming of more widespread use. They can be applied especially in spatial decision support system (SDSS, used in decisions about for nature, environment, forests, agriculture protection, conservation and monitoring, as well as for monitoring of biomass production. Our site selection model was the first step towards planning an agroforestry plantation which uses these integrated technologies to connect the parts with green corridors.

  8. Lake

    Wien, Carol Anne


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

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

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


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

  10. Blue Mountain Lake; An Archeological Survey and an Experimental Study of Inundation Impacts.


    extending back from the bank to the treeline which marks the lake boundary, this site is a very thin scatter of chipped stone. Much of the area was... treeline and river bank. Material Collected: 13 flakes of novaculite and chert, 1 biface fragment. Chronological Position: Unknown 3LO54 Description...AND TYPE Plus Y 12 DIREC- T NEGATIVE N0. DATE TION SIATI DESCRIPTION NUMBER !"ue Nountain Lak e from site 9 1-2-77 SI’ area 74 10 1-2-77 V, Climatic

  11. 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

    Wathne, B.M.


    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.

  12. Unprecedented remote sensing data over King and Rim megafires in the Sierra Nevada Mountains of California.

    Stavros, E Natasha; Tane, Zachary; Kane, Van R; Veraverbeke, Sander; McGaughey, Robert J; Lutz, James A; Ramirez, Carlos; Schimel, David


    Megafires have lasting social, ecological, and economic impacts and are increasing in the western contiguous United States. Because of their infrequent nature, there is a limited sample of megafires to investigate their unique behavior, drivers, and relationship to forest management practices. One approach is to characterize critical information pre-, during, and post-fire using remote sensing. In August 2013, the Rim Fire burned 104,131 ha and in September 2014, the King Fire burned 39,545 ha. Both fires occurred in California's Sierra Nevada. The areas burned by these fires were fortuitously surveyed by airborne campaigns, which provided the most recent remote sensing technologies not currently available from satellite. Technologies include an imaging spectrometer spanning the visible to shortwave infrared (0.38-2.5 μm), a multispectral, high-spatial resolution thermal infrared (3.5-13 μm) spectroradiometer, and Light Detection and Ranging that provide spatial resolutions of pixels from 1 × 1 m to 35 × 35 m. Because of the unique information inherently derived from these technologies before the fires, the areas were subsequently surveyed after the fires. We processed and provide free dissemination of these airborne datasets as products of surface reflectance, spectral metrics and forest structural metrics ( These data products provide a unique opportunity to study relationships among and between remote sensing observations and fuel and fire characteristics (e.g., fuel type, condition, structure, and fire severity). The novelty of these data is not only in the unprecedented types of information available from them before, during, and after two megafires, but also in the synergistic use of multiple state of the art technologies for characterizing the environment. The synergy of these data can provide novel information that can improve maps of fuel type, structure, abundance, and condition that may improve

  13. Remotely sensed surface temperature variation of an inland saline lake over the central Qinghai-Tibet Plateau

    Ke, Linghong; Song, Chunqiao


    Research on surface water temperature (SWT) variations in large lakes over the Qinghai-Tibet Plateau (QTP) has been limited by lack of in situ measurements. By taking advantage of the increased availability of remotely sensed observations, this study investigated SWT variation of Siling Co in central QTP by processing complete MODIS Land surface temperature (LST) images over the lake covering from 2001 to 2013. The temporal (diurnal, intra-annul and inter-annul) variations of Siling Co SWT as well as the spatial patterns were analyzed. The results show that on average from late December to mid-April the lake is in a mixing state of water and ice and drastic diurnal temperature differences occur, especially along the shallow shoreline areas. The extent of spatial variations in monthly SWT ranges from 1.25 °C to 3.5 °C, and particularly large at nighttime and in winter months. The spatial patterns of annual average SWT were likely impacted by the cooling effect of river inflow from the west and east side of the lake. The annual cycle of spatial pattern of SWT is characterized by seasonal reversions between the shallow littoral regions and deep parts due to different heat capacity. Compared to the deep regions, the littoral shallow shoreline areas warms up quickly in spring and summer, and cool down drastically in autumn and winter, showing large diurnal and seasonal variation amplitudes of SWT. Two cold belt zones in the western and eastern side of the lake and warm patches along the southwestern and northeastern shorelines are shaped by the combined effects of the lakebed topography and river runoff. Overall, the lake-averaged SWT increased at a rate of 0.26 °C/decade during 2001-2013. Faster increase of temperature was found at nighttime (0.34 °C/decade) and in winter and spring, consistent with the asymmetric warming pattern over land areas reported in prior studies. The rate of temperature increase over Siling Co is remarkably lower than that over Bangoin

  14. Remote sensing techniques for high mountain environment analysis; Utilizzo di tecniche di telerilevamento per lo studio dell`ambiente in alta montagna

    Antoninetti, Massimo; Pepe, Monica [CNR, Milan (Italy). Istituto di Ricerca sul Rischio Sismico


    Mountain air and water pollution can seriously affect the health of people, animal and plant species. It is very important to understand and calculate the scale of different pollution phenomena. They can start in mountain areas and be exported from them or these areas can be influenced by air and water pollution from far away. In the framework of the Italian EV-K2-CNR Project (High Mountain Scientific and Technologic Researches) a Geographic Information System has been planned to modelling the effects of the interactions between the meteoric waters and the soils (geochemical characteristics, morphology and so on) in the Khumbu Valley, Nepal. The collision between India and Eurasia at the southern margin of Tibet appears to be responsible for the active tectonics throughout much of eastern Asia. The study area, which corresponds to the Phung-Chu / Arun region in the Tibetan Himalayas, has been analysed by photo interpretation of different remotely sensed images.

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

    Iryna Dronova


    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.

  16. R/S Analyses of Some Geochemical Indexes for Tianshuihai Lake Core in West Kunlun Mountain and Their Environmental Implications

    周厚云; 李世杰; 等


    With the decrease of gloal temperature,glacial epoch came over the earth and global climate fluctuated over a great range since the beginning of Quatenary .Paleoclimotologists of various countries have focussed attention to the periodic characteristics and dynamics of climation flucturation in the past many years(Berger,1977;Imbrie and Hays,1984:ding zhongli et al.,1990;Yu zhiwei et al.,1992:Liu Youmei et al.,1996),Although some of the workers have paid their attention to the nonlinear characteristics of the global Quaternary environmental evolution(Nicolis and Nicolis,1984,Lu Houyuan et al.,1993)_,it is worth while to do this kind of work in some special areas in the world,for example the Qinghai-Tibet Plateau.Using R/S analysis,the authors calculated the Hurst indexes H of some geochemical proxies,including organic carbon,FeO,Fe2O3 and FeO/Fe2O3,from the Tianshuihai Lake core in West Kunlun Mountain of the Qinghai-Tibet Plateau,The proxies satisfy the Hurst law with Honrg.carbon=0.735,HFe2O3=0.757,HFeO=0.848and HFeO/Fe2O3=0./646,All the indexs are greater than 0.5,meaning that from 240 to 15ka B.P.,there were some long-run dependencies-persistence in the climatic and environmental evolution around the Tianshuihai Lake area.This is in accordance with the climate there from 240 to 15ka B.P.(Yu Suhua et al.,1996),The paleo-climate and paleo-environment evolution around the Tianshuihai Lake area is of persistence as well as of fluctuation and is a combination of these two components,There are some differences between the four Hurst indexes,Which Probably resulted from the differnet intensitites of Persistence of the four proxies,organic carbon.FeO,Fe2O3 and FeO/Fe2O3,or from the change of drainage system around the Tianshuihai Lake area from opemness to closeness(Li Bingyuan et al.,1991;Sun Honglie,1996:Shi Yafeng et al.1998_).The Qinghai-Tibet plateau was the starter and sensor of the climatic and environmental variation of the surrounding areas(Yao Tandong et al

  17. Assessment of rockfall hazard at Al-Noor Mountain, Makkah city (Saudi Arabia) using spatio-temporal remote sensing data and field investigation

    Youssef, Ahmed M.; Pradhan, Biswajeet; Al-Kathery, Mohamed; Bathrellos, George D.; Skilodimou, Hariklia D.


    Rockfall is one of the major concerns along different urban areas and highways all over the world. Al-Noor Mountain is one of the areas that threaten rockfalls to the Al-Noor escarpment track road and the surrounding urban areas. Thousands of visitors and tourisms use the escarpment track road to visit Hira cave which is located at the top of Al-Noor Mountain. In addition, the surrounding urban areas of Al-Noor Mountain are continuously spreading over the recent years. The escarpment track road and the surrounding urban areas are highly vulnerable and suffers from recurrent rockfall mostly in the rainy season. The steep and highly jointed slope along the different faces of the mountain makes these zones prone to failure due to different actions such as weathering, erosion and anthropogenic effect. Therefore, an attempt has been made in this study to determine the Al-Noor cliff stability, by identifying the unstable areas, and to apply the rockfall simulations. A combination of remote sensing, field study and 2D computer simulation rockfall program were performed to assess surface characteristics of the cliff faces. Bounce height, total and translational kinetic energy, translational velocity, and number of blocks have been estimated. Different unstable zones along the Al-Noor Mountain and escarpment track road were determined using filed investigation and remote sensing based image analysis. In addition the rockfall simulation analysis indicated that rockfall in zone 1 and zone 2 of the Al-Noor Mountain may reach the urban areas, whereas rockfall in zone 3 will not reach the urban areas, and rockfalls along the Al-Noor escarpment track road will have highly impact on the tourists. Proper preventive measures are also suggested to arrest the movement of falling rocks before reaching the urban areas and the Al-Noor escarpment track road. If proper care is taken, then further uncertain rockfall hazards can be prevented.

  18. Detecting river sediments to assess hazardous materials at volcanic lake using advanced remote sensing techniques

    Saepuloh, Asep; Fitrianingtyas, Chintya


    The Toba Caldera formed from large depression of Quaternary volcanism is a remarkable feature at the Earth surface. The last Toba super eruptions were recorded around 73 ka and produced the Youngest Toba Tuff about 2,800 km3. Since then, there is no record of significant volcanic seismicity at Toba Volcanic Complex (TVC). However, the hydrothermal activities are still on going as presented by the existence of hot springs and alteration zones at the northwest caldera. The hydrothermal fluids probably containing some chemical compositions mixed with surficial water pollutant and contaminated the Toba Lake. Therefore, an environmental issues related to the existence of chemical composition and degradation of water clearness in the lake had been raised in the local community. The pollutant sources are debatable between natural and anthropogenic influences because some human activities grow rapidly at and around the lake such as hotels, tourisms, husbandry, aquaculture, as well as urbanization. Therefore, obtaining correct information about the source materials floating at the surface of the Toba Lake is crucial for environmental and hazard mitigation purposes. Overcoming the problem, we presented this paper to assess the source possibility of floating materials at Toba Lake, especially from natural sources such as hydrothermal activities of TVC and river stream sediments. The Spectral Angle Mapper (SAM) techniques using atmospherically corrected of Landsat-8 and colour composite of Polarimetric Synthetic Aperture Radar (PolSAR) were used to map the distribution of floating materials. The seven ground truth points were used to confirm the correctness of proposed method. Based on the SAM and PolSAR techniques, we could detect the interface of hydrothermal fluid at the lake surfaces. Various distributions of stream sediment were also detected from the river mouth to the lake. The influence possibilities of the upwelling process from the bottom floor of Toba Lake were also

  19. Turbidites as indicators of paleotopography, Upper Miocene Lake Pannon, Western Mecsek Mountains (Hungary

    Sztanó Orsolya


    Full Text Available The floor of Lake Pannon covering the Pannonian Basin in the Late Miocene had considerable relief, including both deep sub-basins, like the Drava Basin, and basement highs, like the Mecsek Mts, in close proximity. The several km thick lacustrine succession in the Drava Basin includes profundal marls, basin-center turbidites, overlain by shales of basin-margin slopes, coarsening-upward deltaic successions and alluvial deposits. Along the margin of the Mecsek Mts locally derived shoreface sands and deltaic deposits from further away have been mapped so far on the surface. Recent field studies at the transition between the two areas revealed a succession that does not fit into either of these environments. A series of sandstone a few meters thick occurs above laminated to bioturbated clayey siltstone. The sandstone show normal grading, plane lamination, flat erosional surfaces, soft-sediment deformations (load and water-escape structures and sharp-based beds with small reverse faults and folds. These indicate rapid deposition from turbidity currents and their deformation as slumps on an inclined surface. These beds are far too thick and may reveal much larger volumes of mass wasting than is expected on the 20–30 m high delta slopes; however, regional seismic lines also exclude outcropping of deep-basin turbidites. We suggest that slopes with transitional size (less than 100 m high may have developed on the flank of the Mecsek as a consequence of lake-level rise. Although these slopes were smaller than the usually several hundred meter high clinoforms in the deep basins, they could still provide large enough inertia for gravity flows. This interpretation is supported by the occurrence of sublittoral mollusc assemblages in the vicinity, indicating several tens of meters of water depth. Fossils suggest that sedimentation in this area started about 8 Ma ago.

  20. Wide expansion of glacial lakes in Tianshan Mountains during 1990-2010%近20年天山地区冰湖变化特征

    王欣; 吴坤鹏; 蒋亮虹; 刘时银; 丁永建; 蒋宗立; 郭万钦


    主要基于Landsat TM/ETM+影像等数据,分析1990-2010年来天山地区冰湖变化特征及其对冰川融水径流的影响.近20年来,天山冰湖面积平均以0.689 km2a-1或0.8%a-1的速度扩张,其中一半以上是由东天山(0.352 km2 a-1)贡献的,其次为北天山,面积年均增率为0.165km2a-1,西天山和中央天山的面积年均增率最小,分别为0.089 km2 a-1和0.083 km2 a-1.除在相对较低海拔(< 2900 m)和高海拔(>4100m)范围内冰湖面积出现减少的现象,其他各高度带的冰湖面积均在扩张,其中增率最快的在3500~3900m之间,平均增速达1.6%a-1.冰湖扩张是本区气候变暖和冰川普遍退缩共同作用的结果,以中小规模的冰湖(< 0.6 km2)对冰川退缩响应最为敏感.冰湖扩张能在一定程度上延缓因气候变暖而导致的区域冰川水资源的亏损,每年大约有0.006 Gt的冰川融水滞留在冰湖中,约占天山冰川年消融量的2‰,但也将加剧本区冰湖溃决洪水/泥石流灾害的频次和强度.%The variations and impacts of glacial lakes on glacier melting runoff in the Tianshan Mountains from 1990 to 2010 were assessed on the basis of Landsat TM/ETM images.In the 20 years,glacial lakes in the Tianshan Mountains expanded at a rate of 0.689 km2 a-1 or 0.8% a-1.The glacial lakes in the eastern Tianshan Mountains contributed over half of area expansion at a rate of 0.352 km2 a-1,followed by northern Tianshan Mountains (0.165 km2 a-1),with rates of 0.089 km2 a-1 and 0.083 km2 a-1 in western and central Tianshan respectively.The lake area increased in most of 100-elevation bands except altitudes of <2900 m and >4100 m.The fastest growth bands were observed between 3500 m and 3900 m with an average rate of 1.6% a-1.Both regional warming and wide glacier wastage led to glacial lake expansion,while small and medium-sized (<0.6 km2) lakes were most sensitive to glacier retreat.To some degree,evident glacial lake expansion can slow

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

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


    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

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

    C. Durán


    Full Text Available 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

  3. Experience of developing rural surgical care in a remote mountainous region of Pakistan: Challenges and opportunities

    R Alvi


    Full Text Available Background: Pakistan is one of the most populated countries with a population of 160 million; 67% are rural population but all the tertiary care facilities are concentrated in large cities. The Northern Areas is the most remote region with difficult terrain, harsh weather conditions and the tertiary care hospital at a distance of 600 km with traveling time of 16 h. The Aga Khan Medical Centre, Singul (AKMCS is a secondary healthcare facility in Ghizer district with a population of 132,000. AKMCS was established in 1992 to provide emergency and common elective surgical care. It has strengthened the primary health service through training, education and referral mechanism. It also provided an opportunity for family physicians to be trained in common surgical operations with special emphasis on emergency obstetric care. In addition it offers elective rotations for the residents and medical students to see the spectrum of diseases and to understand the concept of optimal care with limited resources. Methods and Results: The clinical data was collected prospectively using international classification of diseases ICD -9 coding and the database was developed on a desktop computer. Information about the operative procedures and outcome was separately collected on an Excel worksheet. The data from January 1998 to December 2001 were retrieved and descriptive analysis was done on epi info-6. Thirty-one thousand seven hundred and eighty-two patients were seen during this period, 53% were medical, 24% surgical, 16% obstetric and 7% with psychiatric illness. Out of 1990 surgical operations 32% were general surgery, 31% orthopedic, 21% pediatric, 12% obstetric and 4% urological cases; 42% of operations were done under general anesthesia, 22% spinal, 9% intravenous (IV ketamine, 6% IV sedation and 21% under local anesthesia. Six hundred and sixty-two were done in the main operation room including general surgery 337, obstetric 132, urological 67, pediatric 66

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

    Majozi, NP


    Full Text Available Freshwater resources are losing their quality posing a threat to human and aquatic life. Remote sensing has shown potential to monitor these resources. This study aimed to retrieve diffuse attenuation coefficient (Kd), to map euphotic depth (Zeu...

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

    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.


    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

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

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


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

  7. Using a morpho-functional approach to assess phytoplankton dynamics in two adjacent high-mountain lakes: a 10-year survey

    Renata Trevisan


    Full Text Available Colbricon Superiore and Inferiore are two small adjacent high-mountain lakes located in the Paneveggio Natural Park (Italy. The lakes differ by size and depth while sharing the same bedrock setting and catchment basin. Changes in the phytoplankton communities were studied over a 10-years period to individuate which environmental variables would determine the main differences in biotic assemblages across time and between the two lakes.The study was conducted with fortnightly samplings, assessing the density and biomass of algal taxa. Relationships of each of the biological variables with water temperature, pH, conductivity, transparency, water level, previous week rainfall, and relative water column stability were analyzed by correlation and regression analyses, cluster analysis, and by canonical correspondence analysis. The most significant variables resulted air temperature, hydrologic water level and pH. The smaller Colbricon Inferiore had about double the amount of phytoplankton density and biomass than did the larger Colbricon Superiore. The same lake had higher diversity and lower evenness in structure of the phytoplankton community. Notwithstanding their proximity each lake appears to follow independent species composition dynamics, however parallel patterns were interestingly revealed when data were analyzed by pooling taxa into morpho-functional groups. Morpho-functional groups (MFGs 1b, 3a, 6b, 7a, 9b were differentially most abundant in warm periods, while 2c, 3b, 11c, 5e, 10a prevailed in cold years. MFGs 1b, 2d, 3a and 3b were more characteristic of Lake Colbricon Superiore, while Colbricon Inferiore preferentially featured MFGs 5a, 5e, 9a, 9b, 10a, 11a and 8a. The role of the meteo-climatic parameters was pointed out in driving the different patterns observed in the two lakes.

  8. Phytoplankton and littoral epilithic diatoms in high mountain lakes of the Adamello-Brenta Regional Park (Trentino, Italy and their relation to trophic status and acidification risk

    Monica TOLOTTI


    Full Text Available A survey of phytoplankton and littoral epilithic diatom communities was carried out on 16 high mountain lakes in the Adamello- Brenta Regional Park (NE Italy as part of a wider research project aimed to the limnological characterisation of the seldom-studied lakes in this Alpine Region. The regional study was supplemented by the analysis of seasonal variations in two representative lakes. The principal goals of this paper are 1 to identify the most important environmental variables regulating patterns in the species composition of both phytoplankton and littoral diatoms, 2 to evaluate whether these algal communities can be used to improve trophic classification and 3 whether they can facilitate monitoring of diffuse human impacts (e.g. airborne pollution on high altitude lakes. The relevance to monitoring is based on the acid sensitivity of all lakes studied, as indicated by the very low average alkalinity values (4-97 μeq l-1 recorded during the investigation period. Chlorophyll-a concentrations and phytoplankton biovolume recorded in the lakes were very low, with maxima in the deep-water layers and in late summer. Phytoplankton communities were dominated by flagellated algae (Chrysophyceae and Dinophyceae. Several coccal green algae were present, while planktonic diatoms were almost completely absent. Littoral diatom communities were dominated by alpine and acidophilous taxa (mainly belonging to the genera Achnanthes and Eunotia. Trophic classification based on phytoplankton and littoral diatoms, respectively, ascribed all lakes to the oligotrophic range. In both algal communities species indicative of acidified conditions were found. Multivariate analyses indicated that both the regional distribution and seasonal variation of phytoplankton are mainly driven by nutrient concentration. Diatoms are predominantly affected by geochemical characteristics including pH and mineralization level.

  9. Correcting basin-scale snowfall in a mountainous basin using a distributed snowmelt model and remote sensing data

    M. Shrestha


    Full Text Available Adequate estimation of the spatial distribution of snowfall is critical in hydrologic modeling. However, this is a well-known problem in estimating basin-scale snowfall, especially in mountainous basins with data scarcity. This study focuses on correction and estimation of this spatial distribution, which considers topographic effects within the basin. A method is proposed that optimizes an altitude-based snowfall correction factor (Cfsnow. This is done through multi-objective calibration of a spatially distributed, multilayer energy and water balance-based snowmelt model (WEB-DHM-S with observed discharge and remotely sensed snow cover data from the Moderate Resolution Imaging Spectroradiometer (MODIS. The Shuffled Complex Evolution – University of Arizona automatic search algorithm is used to obtain the optimal value of Cfsnow for minimum cumulative error in discharge and snow cover simulations. Discharge error is quantified by Nash–Sutcliffe efficiency and relative volume deviation, and snow cover error was estimated by pixel-by-pixel analysis. The study region is the heavily snow-fed Yagisawa Basin of the Upper Tone River in northeast Japan. First, the system was applied to one snow season (2002–2003, obtaining an optimized Cfsnow of 0.0007 m−1. For validation purposes, the optimized Cfsnow was implemented to correct snowfall in 2004, 2002 and 2001. Overall, the system was effective, implying improvements in correlation of simulated vs. observed discharge and snow cover. The 4 yr mean of basin-average snowfall for the corrected spatial snowfall distribution was 1160 mm (780 mm before correction. Execution of sensitivity runs against other model input and parameters indicated that Cfsnow could be affected by uncertainty in shortwave radiation and setting of the threshold air temperature parameter. Our approach is suitable to correct snowfall and estimate its distribution in poorly-gauged basins, where elevation dependence of snowfall

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

    Kim, Min-Kook; Daigle, John J.


    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 < 0.001). Research implications are explored that relate to the spatial extent of the radial patterns of impact of trampling on vegetation at the site level. Management implications are explored in terms of the spatial strategies used to

  11. Correcting basin-scale snowfall in a mountainous basin using a distributed snowmelt model and remote-sensing data

    Shrestha, M.; Wang, L.; Koike, T.; Tsutsui, H.; Xue, Y.; Hirabayashi, Y.


    Adequate estimation of the spatial distribution of snowfall is critical in hydrologic modelling. However, this is a well-known problem in estimating basin-scale snowfall, especially in mountainous basins with data scarcity. This study focuses on correction and estimation of this spatial distribution, which considers topographic effects within the basin. A method is proposed that optimises an altitude-based snowfall correction factor (Cfsnow). This is done through multi-objective calibration of a spatially distributed, multilayer energy and water balance-based snowmelt model (WEB-DHM-S) with observed discharge and remotely sensed snow cover data from the Moderate Resolution Imaging Spectroradiometer (MODIS). The Shuffled Complex Evolution-University of Arizona (SCE-UA) automatic search algorithm is used to obtain the optimal value of Cfsnow for minimum cumulative error in discharge and snow cover simulations. Discharge error is quantified by Nash-Sutcliffe efficiency and relative volume deviation, and snow cover error was estimated by pixel-by-pixel analysis. The study region is the heavily snow-fed Yagisawa Basin of the Upper Tone River in northeast Japan. First, the system was applied to one snow season (2002-2003), obtaining an optimised Cfsnow of 0.0007 m-1. For validation purposes, the optimised Cfsnow was implemented to correct snowfall in 2004, 2002 and 2001. Overall, the system was effective, implying improvements in correlation of simulated versus observed discharge and snow cover. The 4 yr mean of basin-average snowfall for the corrected spatial snowfall distribution was 1160 mm (780 mm before correction). Execution of sensitivity runs against other model input and parameters indicated that Cfsnow could be affected by uncertainty in shortwave radiation and setting of the threshold air temperature parameter. Our approach is suitable to correct snowfall and estimate its distribution in poorly gauged basins, where elevation dependence of snowfall amount is

  12. Correcting basin-scale snowfall in a mountainous basin using a distributed snowmelt model and remote sensing data

    Shrestha, M.; Wang, L.; Koike, T.; Tsutsui, H.; Xue, Y.; Hirabayashi, Y.


    Adequate estimation of the spatial distribution of snowfall is critical in hydrologic modeling. However, this is a well-known problem in estimating basin-scale snowfall, especially in mountainous basins with data scarcity. This study focuses on correction and estimation of this spatial distribution, which considers topographic effects within the basin. A method is proposed that optimizes an altitude-based snowfall correction factor (Cfsnow). This is done through multi-objective calibration of a spatially distributed, multilayer energy and water balance-based snowmelt model (WEB-DHM-S) with observed discharge and remotely sensed snow cover data from the Moderate Resolution Imaging Spectroradiometer (MODIS). The Shuffled Complex Evolution - University of Arizona automatic search algorithm is used to obtain the optimal value of Cfsnow for minimum cumulative error in discharge and snow cover simulations. Discharge error is quantified by Nash-Sutcliffe efficiency and relative volume deviation, and snow cover error was estimated by pixel-by-pixel analysis. The study region is the heavily snow-fed Yagisawa Basin of the Upper Tone River in northeast Japan. First, the system was applied to one snow season (2002-2003), obtaining an optimized Cfsnow of 0.0007 m-1. For validation purposes, the optimized Cfsnow was implemented to correct snowfall in 2004, 2002 and 2001. Overall, the system was effective, implying improvements in correlation of simulated vs. observed discharge and snow cover. The 4 yr mean of basin-average snowfall for the corrected spatial snowfall distribution was 1160 mm (780 mm before correction). Execution of sensitivity runs against other model input and parameters indicated that Cfsnow could be affected by uncertainty in shortwave radiation and setting of the threshold air temperature parameter. Our approach is suitable to correct snowfall and estimate its distribution in poorly-gauged basins, where elevation dependence of snowfall amount is strong.

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

    Wu, Jialin; Gu, Haoran; Luo, Yongjun


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

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

    Majozi, NP


    Full Text Available of this study was to determine the spectral diffuse attenuation coefficient (K(subd)( )) of the water column, in order to map the euphotic depth (Z(subeu)) of Lake Naivasha, Kenya using the Medium Resolution Imaging Spectrometer (MERIS). Intensive in situ...

  15. Monitored landscape change of Lake Baiyangdian wetland with dynamic reed area based on remote sensing

    Wang, Zhen; He, Lei; Zhang, Shengwei; Lei, Yuping


    Lake Baiyangdian, a largest wetland ecosystem in North China Plain, has dried up on seven occasions since the 1960s. In recent years, more than one billion of cubic meters of water from upstream reservoirs and Yellow river have been transported to the lake to rescue the shrinking wetlands. Since the Lake Baiyangdian was actually composed of 143 small lakes and more than 70 villages with large or small area of cropland, dynamic distribution of aquatic plants in wetland such as reed and associated growth condition of these allowed to monitor the changes of wetland landscape and water quality to support the policy applications of water conveyance and wetland environmental treatment and control. Assisted with ground survey analyses and Landsat TM image, the MODIS 250 m time series Normalized Difference Vegetation Index (NDVI), given its combination of medium spatial and high temporal resolution, were applied to detect the unique rapid growth stage of reed in the spring from adjacent crops such as winter wheat, cotton, and spring maize, of which has a similar phenology in development of leaf area index, and dynamic reed areas were mapped in recent decade. Landscape changes of the wetland were analyzed using maps of reed area and hydrological data.

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

    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...

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

    Kim André Vanselow


    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.

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

    Yang, Guo-Jing; Vounatsou, Penelope; Tanner, Marcel; Zhou, Xiao-Nong; Utzinger, Jürg


    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.

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

    Guo-Jing Yang


    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.


    Svitlana Dovbenko


    Full Text Available Schools in the Ukrainian Carpathian mountain region work in specific conditions. They have original traditions, a special nature of learning and work. Indeed, because of a remote location mountain village school becomes the center for a cultural and spiritual life. Of course, it is related to a present social and economic situation in the country and a slow progress of society. Therefore, we need to look at mountain school with a broader angle, help it in comprehensive development of an individual and ensure an availability of quality education for children living in mountainous areas. Here we should talk about learning as well as laying the foundations for a life success. The international research project Mountain School. Status. Problems. Prospects for Development. Is established to help solve these problems. Precarpathian National University is an active member of the project.

  1. Mineralogy of evaporite deposits on Mars: Constraints from laboratory, field, and remote measurements of analog terrestrial acid saline lakes

    Bridges, N.; Núñez, J. I.; Seelos, F. P., IV; Hook, S. J.; Baldridge, A. M.; Thomson, B. J.


    Remote compositional data from imaging spectrometers such as CRISM, OMEGA, and TES, and high-resolution imagery from MOC, CTX, and HiRISE have provided invaluable information for improving our understanding of the composition and geologic history of the martian surface and identifying potential past and present habitable environments on Mars. Simulated CRISM spectra and summary parameter maps and HiRISE color images were generated using airborne hyperspectral data of two acid-saline lakes in Western Australia. These locations are applicable to Mars, as they contain a suite of clays, sulfates, and salts formed under variable pH and salinity - mineralogies similar to those observed in Noachian and Hesperian terrain. The remote datasets were used to make surface composition predictions which were then verified through field study and sample analysis. We find phyllosilicates intermixed with sulfates in sulfate-rich surfaces exhibit variable spectral responses, even for similar conditions and abundances seen in the field. Where sulfates, such as gypsum and alunite, are found, phyllosilicates are intermixed or reside beneath the surface yet are not always detected. This suggests that geologic complexities may mask phyllosilicate detection at or near the surface on Mars where only sulfates have so far been found.

  2. Support vector machine-based decision tree for snow cover extraction in mountain areas using high spatial resolution remote sensing image

    Zhu, Liujun; Xiao, Pengfeng; Feng, Xuezhi; Zhang, Xueliang; Wang, Zuo; Jiang, Luyuan


    Snow cover extraction in mountain areas is a complex task, especially from high spatial resolution remote sensing (HSRRS) data. The influence of mountain shadows in HSRRS is severe and normalized difference snow index-based snow cover extraction methods are inaccessible. A decision tree building method for snow cover extraction (DTSE) integrated with an efficiency feature selection algorithm is proposed. The severe influence of terrain shadows is eliminated by extracting snow in sunlight and snow in shadow separately in different nodes. In the feature selection algorithm, deviation of fuzzy grade matrix is proposed as a class-specific criterion which improves the efficiency and robustness of the selected feature set, thus making the snow cover extraction accurate. Two experiments are carried out based on ZY-3 image of two regions (regions A and B) located in Tianshan Mountains, China. The experiment on region A achieves an adequate accuracy demonstrating the robustness of the DTSE building method. The experiment on region B shows that a general DTSE model achieves an unsatisfied accuracy for snow in shadow and DTSE rebuilding evidently improves the performance, thus providing an accurate and fast way to extract snow cover in mountain areas.

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

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


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

  4. The impact of the 8.2 ka rapid climate change event on the vegetation and lake ecosystem of the South Carpathian Mountains, Romania

    Ilona PÁL


    Full Text Available Our research is based on pollen-based reconstruction of vegetation composition changes in the Shouthern Carpathians in response to rapid climate changes during the Early Holocene. We demonstrated vegetation response in the northern slope of Retezat Mountains focusing on Lake Brazi. Retezat has a particular importance because of its location and different climatic effects that prevail. Our aim was to examine the vegetation response due to climatic oscillations, which occurred during the Early Holocene. We paid particular attention to the climate change occurring 8200 years ago. We used pollen analysis for the Holocene section of the sediment of Lake Brazi. We investigated the sediment section which covers the so called climatic oscillation at higher resolution.

  5. 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

    Kang Liang


    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.

  6. 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

    Rathore Umesh C.


    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.

  7. Growth pattern research on the modern deposition of Ganjiang delta in Poyang lake basin by spatio-temporal remote sensing images

    Zhou, Hongying; Yuan, Xuanjun; Zhang, Youyan; Dong, Wentong; Liu, Song


    It is of great importance for petroleum exploration to study the sedimentary features and the growth pattern of shoal water deltas in lake basins. Taking spatio-temporal remote sensing images as the principal data source, combined with field sedimentation survey, a quantitative research on the modern deposition of Ganjiang delta in the Poyang Lake Basin is described in this paper. Using 76 multi-temporal and multi-type remote sensing images acquired from 1973 to 2015, combined with field sedimentation survey, remote sensing interpretation analysis was conducted on the sedimentary facies of the Ganjiang delta. It is found that that the current Poyang Lake mainly consists of three types of sand body deposits including deltaic deposit, overflow channel deposit, and aeolian deposit, and the distribution of sand bodies was affected by the above three types of depositions jointly. The mid-branch channels of the Ganjiang delta increased on an exponential growth rhythm. The main growth pattern of the Ganjiang delta is dendritic and reticular, and the distributary channel mostly arborizes at lake inlet and was reworked to be reticulatus at late stage.

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

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


    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.

  9. Stable Isotopes Reveal Nitrogen Loading to Lake Tanganyika from Remote Shoreline Villages

    Kelly, Brianne; Mtiti, Emmanuel; McIntyre, Peter B.; Vadeboncoeur, Yvonne


    Access to safe water is an ongoing challenge in rural areas in Tanzania where communities often lack access to improved sanitation. Methods to detect contamination of surface water bodies, such as monitoring nutrient concentrations and bacterial counts, are time consuming and results can be highly variable in space and time. On the northeast shore of Lake Tanganyika, Tanzania, the low population density coupled with the high potential for dilution in the lake necessitates the development of a sensitive method for detecting contamination in order to avoid human health concerns. We investigated the potential use of nitrogen and carbon stable isotopes of snail tissues to detect anthropogenic nutrient loading along the northeast shore of Lake Tanganyika. δ15N of snails was positively related to human population size in the nearest village, but only for villages with >4000 inhabitants. The areal footprint of villages within their watershed was also significantly correlated with snail δ15N, while agricultural land use and natural vegetation were not. Dissolved nutrient concentrations were not significantly different between village and reference sites. Our results indicate that nitrogen isotopes provide a sensitive index of local nutrient loading that can be used to monitor contamination of oligotrophic aquatic environments with low surrounding population densities.

  10. Stable Isotopes Reveal Nitrogen Loading to Lake Tanganyika from Remote Shoreline Villages.

    Kelly, Brianne; Mtiti, Emmanuel; McIntyre, Peter B; Vadeboncoeur, Yvonne


    Access to safe water is an ongoing challenge in rural areas in Tanzania where communities often lack access to improved sanitation. Methods to detect contamination of surface water bodies, such as monitoring nutrient concentrations and bacterial counts, are time consuming and results can be highly variable in space and time. On the northeast shore of Lake Tanganyika, Tanzania, the low population density coupled with the high potential for dilution in the lake necessitates the development of a sensitive method for detecting contamination in order to avoid human health concerns. We investigated the potential use of nitrogen and carbon stable isotopes of snail tissues to detect anthropogenic nutrient loading along the northeast shore of Lake Tanganyika. δ(15)N of snails was positively related to human population size in the nearest village, but only for villages with >4000 inhabitants. The areal footprint of villages within their watershed was also significantly correlated with snail δ(15)N, while agricultural land use and natural vegetation were not. Dissolved nutrient concentrations were not significantly different between village and reference sites. Our results indicate that nitrogen isotopes provide a sensitive index of local nutrient loading that can be used to monitor contamination of oligotrophic aquatic environments with low surrounding population densities.

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

    Haeberli, W.


    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

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

    E. W. Helbling


    Full Text Available 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

  13. The main features of seasonal variability in the external forcing and dynamics of a deep mountain lake (Redó, Pyrenees



    Full Text Available Lake Redó, a dimictic oligotrophic mountain lake, was monitored for two complete years from July 1996 to July 1998. The main seasonal variations in the physical, chemical and biological parameters are described, with special emphasis on the comparison of external forcing (weather and atmospheric deposition with internal lake dynamics. Annual mean air temperature was estimated to be 3.6 °C. The duration of ice cover on the lake was 4.5 months in 1996/97 and 5.8 months in 1997/98. The lake water was very ionpoor (mean annual conductivity 12 μS cm-1; however, ion concentrations in the lake were higher than in the precipitation, the differences being due mainly to Ca2+ and bicarbonates originating in the catchment. NH4 + was the main ion in the precipitation, with an average concentration of 17 μM, while in the lake it was always below 3 μM. However, the concentration of dissolved inorganic nitrogen always exceeded that of soluble reactive phosphorus by two or three orders of magnitude, so the latter is likely to be the limiting nutrient for phytoplankton growth. Four main production episodes were identified, occurring during spring and autumn overturn, in the upper hypolimnion during summer stratification, and under the ice at the beginning of the ice-covered period. The highest chlorophyll-a concentrations (1.2-2.2 μg l-1 were attained during spring overturn; concentrations of chlorophyll-c were high during both spring and autumn overturn, while chlorophyll-b was comparatively important in the upper hypolimnion during the stratification period. Daphnia pulicaria was the most abundant macrozooplankton species; its abundance was highest during the icecovered period, when its biomass was comparable to the measured sestonic particulate carbon concentration. The Daphnia maximum was associated with higher concentrations of NH4 + and dissolved organic carbon, suggesting that it may play an important role in the pelagic biogeochemical compartment of

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

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


    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

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

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


    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

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

    E. W. Helbling


    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

  17. Water balance modelling in a semi-arid environment with limited in-situ data: remote sensing coupled with satellite gravimetry, Lake Manyara, East African Rift, Tanzania

    D. Deus


    Full Text Available Accurate and up to date information on the status and trends of water balance is needed to develop strategies for conservation and the sustainable management of water resources. The purpose of this research is to estimate water balance in a semi-arid environment with limited in-situ data by using a remote sensing approach. We focus on the Lake Manyara catchment, located within the East African Rift of northern Tanzania. We use remote sensing and a semi-distributed hydrological model to study the spatial and temporal variability of water balance parameters within Manyara catchment. Satellite gravimetry GRACE data is used to verify the trend of the water balance result. The results show high spatial and temporal variations and characteristics of a semi-arid climate with high evaporation and low rainfall. We observe that the Lake Manyara water balance and GRACE equivalent water depth show comparable trends a decrease after 2002 followed by a sharp increase in 2006–2007. Despite the small size of Lake Manyara, GRACE data are useful and show great potential for hydrological research on smaller un-gauged lakes and catchments in semi-arid environments. Our modelling confirms the importance of the 2006–2007 Indian Ocean Dipole fluctuation in replenishing the groundwater reservoirs of East Africa. The water balance information can be used for further analysis of lake variations in relation to soil erosion, climate and land cover/land use change as well as different lake management and conservation scenarios. We demonstrate that water balance modelling can be performed accurately using remote sensing data even in complex climatic settings.

  18. 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

    Zhang L


    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

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

    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.


    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

  20. Plant Diversity of Meishan Mountains near East Lake Scenic Spot in Wuhan City%武汉东湖梅山植物多样性研究

    戴欢; 韩哲元; 何浩


    Species compositions,diversity indexes of plant in green space in Meishan Mountains of Donghu Lake in Wuhan City were analyzed by adopting typical sampling method.Result show that:there are 21 families,29 genera, 34 species in plant in green space of Meishan Mountains of Wuhan City.The floristics in the west and north of the Meishan Mountains are larger than that in eastern and southern of the Meishan Mountains ;Simpson index (D ), Shannon-Weiner index (H )and Pielou index (J )show the same trend,namely the index value of trees> index val-ue of shrubs > index value of herbs;among the plant in Meishan Mountains,the trees whose important values being greater than 10% have nine species,and the shrubs whose important values being greater than 10% have five spe-cies.%采用典型抽样法,对武汉东湖梅山绿地植物的树种组成、多样性指数等进行了调查统计与分析。结果表明:武汉东湖梅山绿地植物共21科29属34种,梅山西部和北部的植物种类多于东部和南部的植物种类;Simpson指数(D)、Shannon—Weiner 指数(H )及 Pielou 指数(J )表现出相同的趋势,即乔木的指数值>灌木的指数值>草本的指数值;东湖梅山植物重要值大于10%的乔木有9种,灌木有5种。

  1. Remote sensing of Myriophyllum spicatum L. in a shallow, eutrophic lake

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


    An aerial 35 mm system was used for the acquisition of vertical color and color infrared imagery of the submergent aquatic macrophytes of Lake Wingra, Wisconsin. A method of photographic interpretation of stem density classes is tested for its ability to make standing crop biomass estimates of Myriophyllum spicatum. The results of film image density analysis are significantly correlated with stem densities and standing crop biomass of Myriophyllum and with the biomass of Oedogonium mats. Photographic methods are contrasted with conventional harvest procedures for efficiency and accuracy.

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

    Michael STURM


    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

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

    Akinola Adesuji Komolafe


    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.

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

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


    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.

  5. 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).

    Geymen, Abdurrahman; Baz, Ibrahim


    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.

  6. GIS based mapping of land cover changes utilizing multi-temporal remotely sensed image data in Lake Hawassa Watershed, Ethiopia.

    Nigatu Wondrade; Dick, Øystein B; Tveite, Havard


    Classifying multi-temporal image data to produce thematic maps and quantify land cover changes is one of the most common applications of remote sensing. Mapping land cover changes at the regional level is essential for a wide range of applications including land use planning, decision making, land cover database generation, and as a source of information for sustainable management of natural resources. Land cover changes in Lake Hawassa Watershed, Southern Ethiopia, were investigated using Landsat MSS image data of 1973, and Landsat TM images of 1985, 1995, and 2011, covering a period of nearly four decades. Each image was partitioned in a GIS environment, and classified using an unsupervised algorithm followed by a supervised classification method. A hybrid approach was employed in order to reduce spectral confusion due to high variability of land cover. Classification of satellite image data was performed integrating field data, aerial photographs, topographical maps, medium resolution satellite image (SPOT 20 m), and visual image interpretation. The image data were classified into nine land cover types: water, built-up, cropland, woody vegetation, forest, grassland, swamp, bare land, and scrub. The overall accuracy of the LULC maps ranged from 82.5 to 85.0 %. The achieved accuracies were reasonable, and the observed classification errors were attributable to coarse spatial resolution and pixels containing a mixture of cover types. Land cover change statistics were extracted and tabulated using the ERDAS Imagine software. The results indicated an increase in built-up area, cropland, and bare land areas, and a reduction in the six other land cover classes. Predominant land cover is cropland changing from 43.6 % in 1973 to 56.4 % in 2011. A significant portion of land cover was converted into cropland. Woody vegetation and forest cover which occupied 21.0 and 10.3 % in 1973, respectively, diminished to 13.6 and 5.6 % in 2011. The change in water body was very

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

    Gongliang Yu


    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.

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

    Neven G. Rostom


    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.

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

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


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

  10. [Estimation and remote sensing inversion of diffuse attenuation coefficient Kd(490) in Lake Taihu in spring based on semi-analytical model].

    Liu, Zhong-Hua; Li, Yun-Mei; Li, Rui-Yun; Lü, Heng; Tan, Jing; Guo, Yu-Long


    Diffuse attenuation coefficient is not only an important optical parameter, but also an important factor of water ecological system. Two datasets measured in April 2009 and May 2010 were firstly used to calculate absorption coefficient [a (490)] and backscattering coefficient [b(b) (490)] at 490 nm, and then, the relationship between b(b) (490) and simulated remote sensing reflectance at different bands of HJ-1 was studied. The semi-analytical model of Kd (490) in Lake Taihu in spring was constructed based on this basis, and it was used to estimate Kd (490) of Lake Taihu via an image of HJ-1 finally. The results show that: 1) The values of a(490) and b(b)(490) can be calculated accurately based on optical closure principle, and the mean absolute percent error (MAPE) of a(490) between calculated and measured is 17.1%. In addition, the backscattering coefficient at 490 nm [b(b) (490)] exponentially relate with the simulated remote sensing reflectance at the fourth band of HJ-1; 2) The semi-analytical model constructed in this study has good accuracy and stability. The MAPE is 21.6% and RMSE is 1.68 m(-1) by comparing inversion result and quasi-synchronous measured data; 3) Kd (490) of Lake Taihu in spring differs a lot in space distribution. The values are relatively smaller in north and east part of Lake Taihu, but larger in west and south part.

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

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


    Element content, loss-on-ignition, chironomid analysis and (210)Pb dating were applied on a sediment core from a subalpine Tatra lake (Popradské pleso) to reveal the response of aquatic biota to eutrophication induced by human activities in the lake catchment. The lead dating indicates that the 0-8 cm section of the core represents the past ca 200 years, ending at ~1814 AD. Comparing the key changes of the proxies with human activities that are historically well documented, four phases of the recent lake development were distinguished: (1) a pre-tourism phase, (2) a phase of increasing touristic activity and early cottage development, (3) a phase of eutrophication, and (4) a phase of post-eutrophication. Neither touristic activity, nor early cottage development around the lake (1st and 2nd phases) had considerable influence on the chironomid assemblage structure or organic content of the lake. The most significant change both in chironomid assemblage structure and loss-on-ignition occurred during the 3rd phase, when a big tourist hotel was built close by the lake and started contaminating it via direct wastewater input. However, the structure of the chironomid assemblage has not changed significantly over time and the dominating taxa remained the same during the whole period. Parallel with the nutrient signal of the paleo assemblage, a secondary signal has been identified as the ratio of rheophilic taxa on total abundance that did not correlate with the sediment's organic content, and is most likely driven by local climatic oscillations. Changes of most of metal elements concentrations reflected rather bigger scale changes of industrial activities than local scale human disturbances. Our results indicate that hydromorphological properties can moderate the impact of organic pollution on the lake biota. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Retrieval of chlorophyll a and suspended solid concentrations by hyperspectral remote sensing in Taihu Lake,China

    YANG Dingtian; PAN Delu; ZHANG Xiaoyu; ZHANG Xiaofeng; HE Xianqiang; LI Shujing


    Chlorophyll a (chl-a) and suspended solid concentrations are two frequently used water quality parameters for monitoring a lake. Traditional measurement of chl-a and suspended solids, requiring laborious laboratory work, which is often expensive and time consuming. Hyperspectral remote-sensing measurement provides a fast and easy tool for estimating water trophic status. In situ hyperspectral data on March 7-8, July 6-7, September 20 and December 7-8, 2004 and the corresponding water chemical data were used to regress the algorithm of water quality parameters. Results showed that the peak of water leaving radiance around 700 nm (R700) varied proportionally with chl-a concentration,and moved to infrared when algal bloom occurred. The reflectance ratio of R702/R685 was well correlated with chl-a when water surface in no algal bloom case and the correlation coefficient was better if absorption of phycocyanin was considered. The reflectance ratio R620/R531 was highly correlated to the concentration of suspended solids. The relationship between suspended solids and other band groups were also compared. Secchi disk depth could be calculated by non-linear correlation with suspended solids concentration.

  13. Assessment of phytoplankton resources suitable for bigheaded carps in Lake Michigan derived from remote sensing and bioenergetics

    Anderson, Karl R.; Chapman, Duane C.; Wynne, Tim T.; Paukert, Craig


    We used bioenergetic simulations combined with satellite-measured water temperature and estimates of algal food availability to predict the habitat suitability of Lake Michigan for adult silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis). Depending on water temperature, we found that bigheaded carp require ambient algal concentrations between 1 and 7 μg chlorophyll/L or between 0.25 × 105 and 1.20 × 105 cells/mL Microcystis to maintain body weight. When the bioenergetics model is forced with the observed average annual temperature cycle, our simulations predicted silver carp bioenergetics predicted annual weight change ranging from 9% weight loss to 23% gain; bighead carp ranged from 68 to 177% weight gain. Algal concentrations b4 μg chlorophyll/L and b200,000 cells/mL were below the detection limits of the remote sensing method. However, all areas with detectable algae have sufficient concentrations of algal foods for bigheaded carp weight-maintenance and growth. Those areas are predominately along the nearshore areas.

  14. Seasonal drainage of supraglacial lakes on debris-covered glaciers in the Tien Shan Mountains, Central Asia

    Narama, Chiyuki; Daiyrov, Mirlan; Tadono, Takeo; Yamamoto, Minako; Kääb, Andreas; Morita, Reira; Ukita, Jinro


    Using field surveys in 2013, 2014, and 2016 plus satellite data from the 1999-2015 period, we analyze the seasonal drainage cycle of supraglacial lakes on seven debris-covered glaciers in the central Tien Shan. We characterize this cycle by the number of lakes and their water levels. The cycle of the Southern Inylchek Glacier starts to increase in the beginning of April, reaches a maximum in May-June, and decreases sharply in June-July. The increase in April to June comes from an inflow of meltwater from snow and ice, and the subsequent decrease arises from a greater connectivity to the englacial drainage network. For the Southern Inylchek Glacier, 94% of the supraglacial lakes that exist and appear during 2013-2015 drain during all three years, indicating that most lakes could connect to the englacial drainage network for three years. Concerning the water level, lakes in close proximity and with the same base-level tend to synchronize their seasonal water levels through the englacial channels. Although the maximum water level of the three-year, field-measured lake is about the same from 2014 through 2016, the date of maximum water level varies between mid-May and mid-June. During this period, the lifetime and size of the supraglacial lakes are controlled by the timing of their connectivity to the englacial drainage network.

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

    Vujko Aleksandra


    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.

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

    Frédéric Satgé


    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.

  17. Monitoring Coastline Change Using Remote Sensing and GIS Technology: A case study of Acıgöl Lake, Turkey

    Temiz, Fatih; Savaş Durduran, S.


    Acıgöl is a lake in Turkey's inner Aegean Region, in an endorheic basin at the junction between Denizli Province, Afyonkarahisar Province and Burdur Province. The lake is notable for its sodium sulphate reserves extensively used in the industry and Turkey's largest commercial sodium sulphate production operations are based here. Coastline changes caused by sediment erosion and accretion have important consequences for coastal ecosystems and coastal communities. Coastlines are the natural borders which separate the water and land. Change of coastline has great importance, therefore it is needed to detect this change and take precautions. In this study, for the purpose of detecting the coastline change of Acıgöl Lake, multispectral Landsat images from the years of 1985, 2000, 2015 were used. Coastline belonging to these years is drawn numerically and coastline change belonging to these years in Acıgöl Lake is provided with the help of Geographic Information Systems and Remote Sensing method and software. After the analysis of the changes, it was determined that there was a significant decline in Acıgöl lake. At the end of the study, significant coastline movements (in some parts more than 200 m) were detected for a 30-year period.

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

    Carolina Doña


    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.

  19. Study on dynamic changes of land desertification in the circum-lake zone of the Qinghai Lake in the past 30 years supported by Remote Sensing and Geographical Information System

    MengJun Hu; WenLi Zhang; AiLi Yang; LiHui Tian; DengShan Zhang


    The circum-lake zone of the Qinghai Lake is one of the most serious regions of desertification on the Qinghai-Tibetan Plateau. Based on Remote Sensing (RS) and Geographical Information System (GIS) techniques, the four sets of remote sensing images acquired in 1976, 1987, 1995, and 2006 were selected to conduct thematic information extraction in 14,300 km2 of land in the circum-lake zone using the Earth Resource Data Analysis System (ERDAS) image and information processing function. In the meantime the off-site interpretation and filed check-correction methods were used to recon-struct the temporal-spatial dynamic changes and differentiation patterns of land desertification in the circum-lake zone in the past 30 years, and based on this, the developmental trend of land desertification in the next 20 years was predicted. The results of the study show that in the past 30 years land desertification in the region experienced a continuous fluctuation between rapid-and slow-development processes in time, while in space it exhibited a few small patchy distributions or sporadic distributions in many places while at the same time, four large sand-dominated distributions stood out and evolved into a circum-lake belt differentiation pattern with a lakeside dike as the connecting line. Due to the integrated effects of climate changes, human activities and artificial rehabilitation, land desertification area in the region in the next 20 years will exhibit an increasing trend in the first 15 years and then increase at a slower rate, and afterward occur in a reverse, decreasing trend.

  20. Tectonic geomorphological characteristics for evolution of the Manas Lake


    Owing to global climatic changes and human activities,the lakes have changed dramatically in the Junggar Basin of Xinjiang in recent 50 years. Based on the remote sensing images from Beijing Satellite No.1 in 2006 together with the measured topographical data in 1999 and other data since the 1950s,this paper analyzes mainly the features of landforms around the Manas Lake and the changes of feeding sources of the lake. The results are as follows:(1) Tectonic movement brought about the fundamental geomorphological basis for lacustrine evolution,and the Manas Lake is one of small lakes broken up from the Old Manas Lake due to tectonic movement and drought climate; the Manas Lake had existed before the Manas River flowed into it in 1915. The geomorphologic evidences for evolution of the Manas Lake include:(a) Diluvial fans and old channels at the north of the lake indicate that the rivers originating from the north mountains of the Junggar Basin had fed the Old Manas Lake and now still feed the lake as seasonal rivers; (b) The Old Manas Lake was fed by many rivers originating from the mountains,except for the Manas River,from the evidence of small lakes around the Manas Lake,old channels,alluvial fans,etc.; (c) The elevations of the alluvial and diluvial fans are near to the 280 m a.s.l. and all of the small lakes and lacustrine plains are within the range of the 280 m a.s.l.,which may prove that the elevation of the Old Manas Lake was about 280 m a.s.l.; (d) Core analysis of the Manas Lake area also indicates that the Manas Lake has existed since Late Pleistocene epoch. (2) Analysis on the feeding relations between the lakes and the lacustrine evolution shows that human activities are one of main driving forces of the lacustrine evolution in recent 50 years,and it is the precondition of restoring and maintaining the lacutrine wetlands in the study area to satisfy the feeding of the Baiyang and Manas rivers to the Manas Lake.

  1. 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

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


    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.

  2. 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

    Skála Ivan


    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.

  3. Source-receptor relationships for speciated atmospheric mercury at the remote experimental lakes area, Northwestern Ontario, Canada

    I. Cheng


    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 adsorption of gaseous Hg (associated with elevated PHg and RGM, crustal/soil emissions, and background pollution. Back trajectory modelling illustrated that a remote site, like the 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.

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

    Kim, Min-Kook; Daigle, John J


    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 vegetation impact and enhance vegetation recovery at the summit loop trail of Cadillac Mountain since 2000. However, the vegetation recovery has been rather minimal and did not reach the level of cover observed during the 1979 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.

  5. Quantitative analysis of land use and land cover changes from the multi-temporal remote sensing data in the Bosten Lake Basin, Chinese Tian Shan

    Maimaiti, A.; Wang, L. M.; Yan, F.; Zhang, J.; Ma, Y. X.


    In this paper, the spatial changes of land use and land cover (LUCC) in Bosten Lake Basin from 1985 to 2015 were analyzed, based on the 3S technology and four periods of remote sensing images in 1985, 1998, 2008 and 2015. The driving force of the LUCC was analyzed quantitatively using principal component analysis (PCA) method. The results showed that there was a wide change of LUCC in the Bosten Lake Basin in the past 30 years. During this periods, natural grassland decreased with a rate of 62.6 km2/a, while cultivated land and residential land increased with a rate of 28.9 km2/a. The rapid expansion of cultivated land was the result of natural grassland and unused land reclamation. Meanwhile, other land use types changed slightly. The results of PCA analysis indicated that the LUCC change was result of the interaction of human activity (social and economic factors) and natural environmental changes (climate change). Therefore, it is necessary to consistently improve the natural environment of Bosten Lake Basin. This study can provide stable basis of the theory and practice for sustainable development of Bosten Lake Basin.

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

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


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

  7. Quantifying the Effect of Thinning Vegetation on Evapotranspiration in a Mountainous Watershed through Remote Sensing: Improving Water Balance Estimates for Managed Aquifer Recharge

    Revelle, P.; Hendrickx, J. M. H.


    A long-term water balance study in an experimental watershed of the Sacramento Mountains in New Mexico monitors the impact of thinning vegetation on groundwater recharge. The study objective is to evaluate if thinning forest vegetation will increase groundwater recharge in the mountains to provide larger regional flows to aquifers in surrounding basins. In the semi-arid Southwest, evapotranspiration (ET) makes up 75 to 95% or more of the total water budget. The variability of daily vegetation transpiration and solar radiation with time of year and the effects of complex terrain create a seasonal and spatial variability of ET that is not well quantified in mountainous regions. Through applying the remote sensing model METRIC (Mapping Evapotranspiration with High Resolution and Internalized Calibration) to satellite imagery from the LANDSAT satellite, we calculate high-resolution maps of ET for the Sacramento Mountains watershed area to quantify spatially-distributed estimates of ET before and after thinning to provide improved estimates for determining the water balance and the effect on recharge. METRIC calculates ET through applying an energy balance spatially across an image to estimate ET for each pixel (30m x 30m). Differences in ET are calculated between thinned and control plots in the watershed before and after thinning with the net impact of thinning on ET for an image determined with standard statistical tests following a Before-After Control-Impact (BACI) approach commonly used in environmental impact assessment studies. Estimates of ET from METRIC indicate a net decrease in ET in the first year after thinning for all of the thinned plots but show significant variability (~2 - 12 %) between areas with different terrain characteristics. The impact of surface parameters such as slope, aspect, or albedo among others are currently being examined using multivariate statistical analysis methods to improve the understanding of the spatial and temporal

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

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


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

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

    T. Bolch


    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. Analysis of climate change impacts on surface energy balance of Lake Huron (estimation of surface energy balance components: Remote sensing approach for water -- atmosphere parameterization)

    Petchprayoon, Pakorn

    The purpose of this thesis was to investigate the physical processes of energy exchange between the water surface and atmosphere of Lake Huron in order to explain the processes behind such changes in long-term water levels and to monitor their spatial and temporal fluctuations. The lake surface water temperature and the four components of surface energy balance, including net radiation, latent heat, sensible heat, and heat storage, as well as evaporation rate, were estimated using the daily remotely sensed data from eleven years (2002--2012) with a multi-spatial resolution of 1 km to 5 km using the Moderate Resolution Imaging Spectroradiometer (MODIS) on board Terra satellite, together with in-situ measurements. The regression analysis of the entire lake daily mean water surface temperature revealed a positive trend of 0.1 °C per year, indicating that the lake surface temperature increased by 1.1°C during the period 2002-2012. The warming rate was found to be greatest in the deepest areas of the lake, with a statistically-significant correlation between warming rate and depth. The four components of surface energy balance showed temporal and spatial heterogeneities. There were strong seasonal patterns for all of the components, which were very high in summer and low in winter for net radiation and heat storage. In contrast, the latent heat and sensible heat were very high in the winter and very low in the summer. Approximately 70% of the annual mean 30 min evaporation occurred during the fall and winter seasons, whereas the lowest evaporation rate occurred in March, which was only 3% of the annual mean of 30 min evaporation. There was an increase in the evaporation rate of approximately 1.4 mm m-2 over the 2005--2012 observation period, the water level decreased by 0.04 m during the period 2002--2012, and there was a decrease in total water storage by 1.18 cm during the entire study period (2004--2012). There was obviously a negative correlation between lake

  11. Understand mountain studies from earthquake


    @@ The Sichuan earthquake on 12 May was the most devastating one to hit China over the past 60 years or so. As the affected were mostly mountainous areas, serious damages were caused by various secondary disasters ranging from mountain collapse to the formation of quake lakes. This leaves Prof. DENG Wei, director-general of the Institute of Mountain Hazards and Environment, CAS, much to think about, and he is calling for strengthening studies on mountain science.

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

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


    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

  13. Atmospheric processes of organic pollutants over a remote lake on the central Tibetan Plateau: implications for regional cycling

    Ren, Jiao; Wang, Xiaoping; Wang, Chuanfei; Gong, Ping; Yao, Tandong


    Atmospheric processes (air-surface exchange, and atmospheric deposition and degradation) are crucial for understanding the global cycling and fate of organic pollutants (OPs). However, such assessments over the Tibetan Plateau (TP) remain uncertain. More than 50 % of Chinese lakes are located on the TP, which exerts a remarkable influence on the regional water, energy, and chemical cycling. In this study, air and water samples were simultaneously collected in Nam Co, a large lake on the TP, to test whether the lake is a secondary source or sink of OPs. Lower concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were observed in the atmosphere and lake water of Nam Co, while the levels of polycyclic aromatic hydrocarbons (PAHs) were relatively higher. Results of fugacity ratios and chiral signatures both suggest that the lake acted as the net sink of atmospheric hexachlorocyclohexanes (HCHs), following their long-range transport driven by the Indian monsoon. Different behaviours were observed in the PAHs, which primarily originated from local biomass burning. Acenaphthylene, acenaphthene, and fluorene showed volatilization from the lake to the atmosphere, while other PAHs were deposited into the lake due to the integrated deposition process (wet/dry and air-water gas deposition) and limited atmospheric degradation. As the dominant PAH compound, phenanthrene exhibited a seasonal reversal of air-water gas exchange, which was likely related to the melting of the lake ice in May. The annual input of HCHs from the air to the entire lake area (2015 km2) was estimated as 1.9 kg yr-1, while input estimated for ∑ 15PAHs can potentially reach up to 550 kg yr-1. This study highlights the significance of PAH deposition on the regional carbon cycling in the oligotrophic lakes of the TP.

  14. Vulnerability assessment of Glacial Lake Outburst Floods using Remote Sensing and GIS in North Sikkim (India), Eastern Himalaya

    Aggarwal, Suruchi; Probha Devi, Juna; Thakur, Praveen Kumar; Rai, Suresh Chand


    Glacial lake outburst floods (GLOFs) occur when glacier melt water dammed by a moraine is released in short time. Such floods may lead to disastrous events posing, therefore, a huge threat to human lives and infrastructure. A devastating GLOF in Uttarakhand, India, on 17 July 2013 has led to the loss of all villages in a stretch of 18 km downstream the lake and the loss of more than 5000 lives. The present study evaluates all 16 glacial lakes (with an area >0.1 km²) in the Thangu valley, northern Sikkim (India), eastern Himalaya, with respect to potential threats for the downstream areas. The hazard criteria for the study include slope, aspect and distance of the respective parent glacier, change in the lake area, dam characteristics and lake depth. For the most hazardous lakes, the socio-economic conditions in the downstream areas (settlements and infrastructure) are analysed regarding the impact of potential GLOFs. For the vulnerability analysis, we used various satellite products including LANDSAT, RESOUCESAT-1 and 2, RISAT-1 imageries and ASTER GDEM covering the period from 1977 to 2014. For lake mapping, we applied the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Snow Index (NDSI). A Land Use Land Cover (LULC) map of the study area showing in-situ observations is serving as driving factor for the vulnerability analysis. The results of the study show that almost all evaluated glacial lakes were expanding during the study period (1977-2014). Combining the hazard criteria for the lakes, 5 of the 16 studied glacial lakes are identified as highly hazardous. In the downstream area, there are two villages with 200 inhabitants and an army camp within the zone of highest vulnerability. The identified vulnerability zones may be used by the local authorities to take caution of the threatened villages and infrastructure and for risk analysis for planned future hydropower plants.

  15. Verification of glacial lake outburst debris flow events in Jincuo Lake of Tibet based on remote sensing image analysis%基于遥感图像分析对金错冰川湖溃决泥石流事件的验证

    郭兆成; 童立强; 周成灿; 赵振远


    In mountainous areas of Tibet,glacial lake outburst debris flow is one of the main disasters,bringing devastating destruction to downstream settlements and infrastructures,such as roads,bridges and water facilities.Glacial lake outburst debris flow has long drawn great attention;nevertheless,because of the cold climate,steep terrain and terrible traffic condition which bring inconvenience to field investigation,very instfficient real-time literature data or some records inconsistent with the facts have been obtained for most of the glacial lake outburst events.Remote sensing images can really record the traces related to glacial lake outburst debris flow.Based on the high spatial resolution images of RapidEye and the multi-temporal images of Landsat MSS and TM,the authors analyzed the glacial lake outburst debris flow event that occurred in 1982 in Dinggye County,Tibet,which was reported by Lyu Ruren and Cheng Zunlan et al.Through remote sensing interpretation and analysis of dynamic changes of the glacial lake outburst debris flow event,the authors hold that the "Jincuo Lake outburst debris flow event" was actually induced by Yindapucuo Lake outburst.In the field investigation the authors found that Jincuo moraine was not destroyed by debris flow,and there was neither large U-type gully nor new debris flow accumulation settled in its downstream site,which confirmed the analysis of remote sensing.The results show that high resolution and multi-temporal remote sensing images can effectively improve the accuracy of investigation for geological hazards in dangerous areas.%突发冰川终碛湖(简称“冰湖”)溃决泥石流/洪水是西藏高山冰湖分布区的一种山地灾害,极易给下游地区的居民及公路、桥梁、水利水电等基础设施带来毁灭性灾害.多年来,对冰湖溃决泥石流/洪水的研究受到了高度重视;但高山高寒和艰险的地形及交通条件,给冰湖溃决泥石流灾害的实地调查带来不便,大部

  16. Detecting changes in surface water area of Lake Kyoga sub-basin using remotely sensed imagery in a changing climate

    Nsubuga, F. W. N.; Botai, Joel O.; Olwoch, Jane M.; Rautenbach, C. J. deW; Kalumba, Ahmed M.; Tsela, Philemon; Adeola, Abiodun M.; Sentongo, Ausi A.; Mearns, Kevin F.


    Detection of changes in Earth surface features, for example lakes, is important for understanding the relationships between human and natural phenomena in order to manage better the increasingly scarce natural resources. This work presents a procedure of using modified normalised difference water index (MNDWI) to detect fluctuations of lake surface water area and relate it to a changing climate. The study used radiometrically and geometrically rectified Landsat images for 1986, 1995 and 2010 encompassing the Kyoga Basin lakes of Uganda, in order to investigate the changes in surface water area between the respective years. The standard precipitation index (SPI) and drought severity index (DSI) are applied to show the relationship between variability of surface water area and climate parameters. The present analysis reveals that surface water area fluctuation is linked to rainfall variability. In particular, Lake Kyoga sub-basin lakes experienced an increase in surface water area in 2010 compared to 1986. This work has important implications to water resources management for Lake Kyoga and could be vital to water resource managers across Ugandan lakes.

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

    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.

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

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


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

  19. Microbial plankton assemblages, composition and biomass, during two ice-free periods in a deep high mountain lake (Estany Redó, Pyrenees

    Silvana HALAC


    Full Text Available Microbial plankton composition and biomass were monitored for two ice-free periods in a deep oligotrophic high-mountain lake (Redó, Pyrenees. Phytoplankton dominated microbial biomass, while the relationship between total water-column-integrated autotrophic and heterotrophic biomass ranged from 1.5 to 6.5 (an average of 4.4. Heterotrophic biomass was dominated by bacteria (an average of 47 %, but heterotrophic nanoflagellates and, to a lesser degree, ciliates occasionally constituted a sizeable proportion. In general, the microbial biomass ratios were 10:2:2:1 for PHY:BAC:HNF:CIL. About one hundred eukaryotic species were found, although most of them in low abundance and frequency. Phytoplankton biomass was dominated by flagellated chrysophytes and dinoflagellates (an average of 40 and 32% respectively; occasionally cryptophytes (in deep layers and chlorococcal chlorophytes (during the autumn mixing period were also significant. In the two years sampled, the maximum phytoplankton diversity was observed during the autumn mixing period. Heterotrophic flagellate biomass was dominated by chrysophytes (78% on average, but sporadically a non-identified species reached high abundances. Oligotrichs, (an average of 43% of total ciliate biomass dominated the ciliate community, still other groups (gymnostomatida and prostomatida were also significant. Bacteria biomass was largely homogeneous throughout the two periods, but size segregation was observed especially when the lake was stratified, with larger bacteria appearing in the upper layers. The highest planktonic microbial biomass occurred during the mixing periods, mainly during spring. But no clear relationships were found between the temporal distribution of bacteria, phytoplankton, heterotrophic flagellate and ciliate biomass.

  20. 偏远山区教师心理健康状态调查%An investigation on the mental health of teachers in remote mountain areas



    在人际敏感、抑郁、焦虑因子上得分都高于男教师,差异有显著性(P<0.05).⑤≥30岁的教师阳性项目均分、躯体化、恐怖等因子的得分高于30岁以下的教师,差异有显著性(P≤0.01).结论:山区教师心理问题检出率较高,集中表现在强迫、人际敏感、焦虑、抑郁、躯体化等方面.山区教师症状自评量表总分、总均分、阳性项目平均分以及各因子得分均明显高于国内正常人群.女教师心理问题发生率高于男教师.30岁以上的教师心理健康水平较差.%BACKGROUND: The mental health of primary school teachers who have been working in remote mountain areas for a long time can be affected by the environment and conditions there.OBJECTIVE: To analyze the present mental health of mountain-area teachers to seek countermeasures of raising their mental health level.DESIGN: An investigation of random sampling questionnaires was carried out with the primary school teachers in remote mountain areas as observational subjects.SETTING: Department of Education, Xinzhou Teachers' Training Institute.PARTICIPANTS: From December 2003 to February 2004, 182 teachers who were randomly sampled from the 28 most remote mountain schools selected from seven counties and cities such as Wutai, Shenchi and Hequ in Shanxi Province, were selected as investigation subjects.METHODS: The self-assessed/measured symptom scale was used to assess the mental health of mountain area teachers. The scale was made up of 90 items, including 9 factors such as somatic disorder, obsessive disorder, interpersonal sensitivity, anxiety, depression, hostility, horror, paranoia,and psychoticism. There were 5 scaling levels: 1 shows 'never', 2 shows'mild', 3 shows 'moderate', 4 shows 'rather serious' and 5 shows 'severe'. Evaluation standard: If the factor score ≥ 2, they had mild symptoms; if any factor score ≥ 3, they were regarded as probably having mental problems above moderate degree. The major

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

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


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

  2. 如何有效开展边远山区农村学校初中物理实验教学%How to Effectively Carry out Remote Mountainous Countryside Junior Middle School Physics Experiment Teaching

    唐才华; 李万琼


    In the remote mountainous rural junior high school physics teaching, the physics experiment is the best way for student effectively learning the junior middle school physics knowledge.%在边远山区农村学校初中物理教学中,进行物理实验是学生有效学习初中物理知识的最好方法。

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

    Federico Frassy


    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.

  4. Spatio-temporal variability of the snow cover in different Mediterranean mountain regions from in situ and remote sensing data

    Gascoin, Simon; López-Moreno, Juan Ignacio; Herrero, Javier; Sproles, Eric; Hanich, Lahoucine; Boudhar, Abdelghani; Pons, Marc; Alonso-González, Esteban; Musselman, Keith


    The snow cover is an essential water resource in many regions with a Mediterranean climate. In the mountainous areas of these regions, in situ snow measurements are often too sparse to cover the range of spatial variability due to the topography. In contrast, satellite snow products are not sufficient to understand the processes governing the snowpack evolution. The combination of both data sources is useful to understand the effects of climate variability on the snow cover. Here we gathered the data of several high-elevation, snow-observing stations in the Pyrenees (Spain, Andorra), High-Atlas (Morocco), Sierra Nevada (Spain), Sierra Nevada (USA) and the Andes of Norte Chico (Chile) to run a point-scale snowpack energy-balance model. We extracted and gapfilled the MODIS snow product over 2000-2015 around each station to determine the mean snow cover duration as a function of elevation. The results of the energy-balance model highlight the importance of the snow sublimation, which amounts from 10% to 30% of the mean annual solid precipitation in these sites. The MODIS data indicate that the relationship between the snow cover duration and the elevation is almost entirely explained by the distance from of each site to the equator, which further indicates that radiation and humidity are important drivers of the snowpack dynamics. These factors should not be overlooked in the projections of the melt water contribution to runoff under future climate conditions.

  5. Analysis of the changes of vegetation coverage of western Beijing mountainous areas using remote sensing and GIS.

    Liu, Liangyun; Jing, Xia; Wang, Jihua; Zhao, Chunjiang


    Mentougou District acts as a crucial component in the ecological buffer in western Beijing mountainous areas, Beijing, China. Using two Landsat MSS/TM images acquired on July 14, 1979 and July 23, 2005, the vegetation coverage of Mentougou District was calculated based on normalized difference vegetation index and spectral mixture analysis (NDVI-SMA) model. Its temporal and spatial changes were analyzed according to digital elevation model (DEM) image, social and economic data. The results showed that the vegetation coverage decreased from 76.4% in 1979 to 72.7% in 2005. Vegetation degradation was probably the result of human disturbance, such as outspreading of resident areas, and coal and stone mining activities, while vegetation restoration might be contributed by the combined effects of both natural processes and ecological construction effort. Vegetation changes were closely related to topographical characteristics. Plants at high altitude were more stable and less degraded than the plants at low altitude, while the plants on steep slope or northwest aspect were more vulnerable to degradation. During the period of 26 years, landscape appeared to become more fragmental, and ecological quality of the land seemed deteriorated sharply in that highly-covered vegetation area has been decreased by 24%.

  6. Impact of satellite-based lake surface observations on the initial state of HIRLAM. Part I: evaluation of remotely-sensed lake surface water temperature observations

    Homa Kheyrollah Pour


    Full Text Available Lake Surface Water Temperature (LSWT observations are used to improve the lake surface state in the High Resolution Limited Area Model (HIRLAM, a three-dimensional numerical weather prediction (NWP model. In this paper, satellite-derived LSWT observations from the Moderate Resolution Imaging Spectroradiometer (MODIS and the Along-Track Scanning Radiometer (AATSR are evaluated against in-situ measurements collected by the Finnish Environment Institute (SYKE for a selection of large- to medium-size lakes during the open-water season. Data assimilation of these LSWT observations into the HIRLAM is in the paper Part II. Results show a good agreement between MODIS and in-situ measurements from 22 Finnish lakes, with a mean bias of −1.13°C determined over five open-water seasons (2007–2011. Evaluation of MODIS during an overlapping period (2007–2009 with the AATSR-L2 product currently distributed by the European Space Agency (ESA shows a mean (cold bias error of −0.93°C for MODIS and a warm mean bias of 1.08°C for AATSR-L2. Two additional LSWT retrieval algorithms were applied to produce more accurate AATSR products. The algorithms use ESA's AATSR-L1B brightness temperature product to generate new L2 products: one based on Key et al. (1997 and the other on Prata (2002 with a finer resolution water mask than used in the creation of the AATSR-L2 product distributed by ESA. The accuracies of LSWT retrievals are improved with the Key and Prata algorithms with biases of 0.78°C and −0.11°C, respectively, compared to the original AATSR-L2 product (3.18°C.

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

    Matthews, MW


    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...

  8. Trophic Status, Ecological Condition and Cyanobacteria Risk of New England Lakes and Ponds Based on Aircraft Remote Sensing.

    Aircraft remote sensing of freshwater ecosystems offers federal and state monitoring agencies an ability to meet their assessment requirements by rapidly acquiring information on ecosystem responses to environmental change for water bodies that are below the resolution of space...

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

    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


    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.

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

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


    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.

  11. Geochemical Features of the Hubin Spring Gases from the Northern Caldera Lake of the Tianchi Volcano, Changbai Mountains

    Gao Ling; Shangguan Zhiguan; Wei Haiquan; Zhao Ciping


    This paper deals with geochemical features of gas emitted from the Hubin Springs. The Hubin Springs zone, a strong thermal emission zone, is are locatedd at the north edge of the Tianchi caldera lake. Very young deposits with uncertain eruption date are found on the top area of the Tianwenfeng, which might have been formed in one of the recent eruptions or the Millennium Eruption. It is of significance to study the geochemistry features of the emitting gas from the Hubin Springs to understand the activities of the Tianchi Volcano. This paper systematically sampled and analyzed the gases emitted from the Hubin Springs and discussed their geochemistry features. The results show that there is a high content of deep derived gases, such as CO2, He, CH4 and Ar in Hubin Springs zone. The isotopic ratio of He lies between 4. 18 and 5. 95 Ra. The averaged mantle derived gas content calculated from the ^4He/2^20Ne ratio and He content reaches 67.1%. All these show that the Hubin Springs are located on a special belt of deep gases released in high intensity and large scale. The spatial distribution of Helium isotope is characterized by concavity, showing that this special area may be related to the volcanic edifice. It is highly possible that the released gases represent the residual gas samples of the latest eruptions from the Tianchi Volcano. However more detailed studies are demanded.

  12. 基于多源遥感数据的非洲乍得湖水面变化监测%Remote sensing analysis on lake area variation of Lake Chad

    刘甜甜; 刘荣高; 葛全胜


    Lake Chad,on the border of the Sahara desert in central Africa,is well known for its high sensitivity to hydroclimatic events.Over the last 40 years,Lake Chad,once the sixth largest lake in the world,has shrunk by more than 90% in area.In this paper,variations of the open water areas,extracted from multi-source remote sensing data during 1973-2012,are analyzed.The results showed that in general Lake Chad was getting smaller and smaller during 1973-2012.Between 1973 and 1975 its area sharply reduced by about 71%.From then on its area ranges from 2000 km2 to 5000 km2.In order to validate the reliability of the trends,this paper first compares it with Birkett's results to analyze area accuracy,and next compares the results of MODIS with Landsat and AVHRR to validate the comparability of multi-source data,and last monitors monthly variation of Lake Chad area to validate the feasibility of multi-temporal data.Meteorological data analysis showed that the area of Lake Chad and the fluctuation of annual precipitation were in good correlation.Secondly,a large number of reservoirs built are another important cause of area reduction.Lastly,the Great Barrier that divided the lake into two smaller lakes has made it more vulnerable to water loss.%乍得湖位于中非撒哈拉沙漠边界,是非洲重要的淡水湖,湖面大小对气候变化高度敏感.近40年,由于干旱等自然灾害和大规模灌溉等人为因素的影响,乍得湖面积急剧减少,受到广泛关注.本文利用多种光学遥感数据提取1973-2012年乍得湖面积,分析其变化趋势和驱动机制.结果表明,1973-2012年间乍得湖面积总体上在变小,1973-1975年间乍得湖面积急剧减少了约71%,1975-2012年面积在2000~5000km2范围内波动.为验证变化趋势的可靠性,本文利用MODIS影像与同期Landsat和AVHRR影像的提取结果进行比较,来检验多源数据的可比性;通过MODIS影像监测乍得湖面积的月变化,来检验所选数


    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...

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

    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...

  15. The influence of climate change on the accumulation of polycyclic aromatic hydrocarbons, black carbon and mercury in a shrinking remote lake of the southern Tibetan Plateau.

    Lin, Hai; Wang, Xiaoping; Gong, Ping; Ren, Jiao; Wang, Chuanfei; Yuan, Xiaohua; Wang, Lei; Yao, Tandong


    A sediment core from a remote lake, Pumoyum Co, located in the southern TP, was analyzed for polycyclic aromatic hydrocarbons (PAHs), black carbon (BC) and mercury. Concentrations ranged from 30 to 229ng/g for PAHs, 0.46 to 1.48mg/g for BC and 10 to 30ng/g for mercury. Significant correlations were found among the concentrations of PAHs, BC and mercury, suggesting the sources of these pollutants to be similar; mainly from combustion processes. Further diagnosis of the likely sources of BC and PAHs suggested that petroleum combustion has been one of the increasing sources in the last few decades, but biomass burning remains the dominant source of these pollutants. The historic trends of the three pollutants closely followed historic BC emission trends from Europe (before 1970) and southern Asia (after 2000). With economic development in southern Asia, concentrations of pollutants in the sediments of Pumoyum Co have increased during the past decade. However, the accumulation fluxes of the pollutants during that period remained stable, which may be due to the recent low precipitation and less catchment erosion of Pumoyum Co (experienced a drier climate and shrinking of lake area). Copyright © 2017 Elsevier B.V. All rights reserved.

  16. The use of Remotely Piloted Aircraft System (RPAS) for geological monitoring and mapping in mountain area: test and results

    Taddia, Glenda; Piras, Marco; Forno, Gabriella M.; Gattiglio, Marco; Lingua, Andrea; Lo Russo, Stefano


    Geological mapping is an interpretive process involving multiple types of information, from analytical data to subjective observations, collected and synthesized by a researcher. With field experience, geologists generally develop effective personal styles of relatively efficient mapping. Each geologic map, regardless of scale, requires a certain level of field mapping, where data are recorded on a topographic map and on aerial images, with notes in a field book. Traditionally, geological elements are hand-transferred to a cartography, on which the final map is prepared for publication using known cartographic techniques. Cartography and topographic support are traditionally produced with aerial photogrammetry method, but nowadays, the coming of the Remotely Piloted Aircraft System (RPAS) or so called UAV (Unmanned Aerial Vehicle) can help the geologist to produce similar support, but reducing cost, increasing the productivity , to have a more flexible system and more. In this case, the commercial fixed-wing system EBEE has been tested by producing a dense digital surface model (DDSM) of the bedrock, Quaternary sediments and landforms in a sector of the alpine Rodoretto Valley, a tributary of the Germanasca Valley (northwestern Italy). The Germanasca Valley is located along the north-south tectonic thrust between the Dora Maira Massif, which outcrops on the valley's right side and the Greenstone and Schist Complex visible on the left side. These nappe systems include the Penninic Domain (Lower, Medium and Upper Penninic units) and the Piedmont Zone. The landforms and surficial sediments in this valley have resulted from the combinate effects of the Quaternary alpine glacial phases and deep-seated gravitative slope deformations. In the area of investigation only monotonous calcshists of the Greenstone and Schist Complex (GS) occur, with a regional foliation dipping 20-30° to N30E and the examined area is located between 2500 m and 1760 m. The area appears elongated

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

    Robinson I. Negrón-Juárez


    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

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

    Karen Anderson


    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

  19. Unexpected response of high Alpine Lake waters to climate warming.

    Thies, Hansjörg; Nickus, Ulrike; Mair, Volkmar; Tessadri, Richard; Tait, Danilo; Thaler, Bertha; Psenner, Roland


    Over the past two decades, we have observed a substantial rise in solute concentration at two remote high mountain lakes in catchments of metamorphic rocks in the European Alps. At Rasass See, the electrical conductivity increased 18-fold. Unexpectedly high nickel concentrations at Rasass See, which exceeded the limit in drinking water by more than 1 order of magnitude, cannot be related to catchment geology. We attribute these changes in lake water quality to solute release from the ice of an active rock glacier in the catchment as a response to climate warming. Similar processes occurred at the higher elevation lake Schwarzsee ob Sölden, where electrical conductivity has risen 3-fold during the past two decades.

  20. Observed and simulated hydroclimatology using distributed hydrologic model from in-situ and multi-satellite remote sensing datasets in Lake Victoria region in East Africa

    S. I. Khan


    Full Text Available Floods and droughts are common, recurring natural hazards in East African nations. Studies of hydro-climatology at daily, seasonal, and annual time scale is an important in understanding and ultimately minimizing the impacts of such hazards. 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 physically-based, distributed hydrologic model, with in-situ and multi-satellite remote sensing datasets. Moreover, the hydrologic capability of remote sensing data such as TRMM-3B42V6 was tested in terms of reconstruction of the water cycle components. The spatial distribution and time series of modeling results for precipitation (P, evapotranspiration (ET, and change in storage (dS/dt 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 early June. The hydrologic model captured the spatial variability of the soil moisture storage. The spatially distributed model inputs, states, and

  1. 山地型湿地公园景观营造探析——以山西云竹湖湿地为例%Mountain Wetland Park Landscape Construction: A Case Study of Yunzhu Lake Wetland Park



    Based on analysis of the features of Mountain Wetland Park and the landscape resources of Yunzhu Lake Wetland Park in Shanxi, the idea of constructing Mountain Wetland Park Landscape was proposed, which covers four aspects, conservation and utilization, science education, eco-tourism, and recreation. The method and content of Mountain Wetland Park Landscape Construction were systematically illustrated in order to provide a basis for similar mountain wetlands in China.%结合山西云竹湖湿地公园案例,在对山地型湿地公园特征和云竹湖湿地公园景观资源分析的基础上,针对性地提出了山地型湿地公园景观营造理念,从保护利用、科普教育、生态观光、休闲娱乐4大功能入手,系统探析了山地型湿地公园景观营造方法及内容,以期对我国山地型湿地公园景观营造提供借鉴.

  2. 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

    Hans W Linderholm


    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.

  3. Research on The Method of Computer Visual Remote Localization with Lost Tourist in Mountain%深山旅游失踪者计算机视觉远程定位方法研究



    在深山旅游探险中由于地理状况复杂,灌木密集,浓雾迷绕,对深山旅游失踪人群进行准确定位困难较大。传统方法中使用远程遥感技术对失踪者进行定位,在深山浓雾笼罩等恶劣天气下,定位效果较差。提出一种基于大气激光通信的远程遥感计算机视觉定位方法,利用空地大气激光通信特征,使用小波边缘检测算法对遥感视觉图像进行特征提取,实现对深山旅游失踪者的定位标记。仿真实验表明,采用该方法进行深山人体目标定位,能有效提取人体目标遥感视觉特征,定位准确,为深山搜索救援提供了很好的理论基础。%In the mountains of travel and exploration in complex due to the geographical conditions such as shrubs, dense fog. The mountain tourism disappeared persons for accurate positioning is difficult. To locate the missed persons, the re-mote sensing technology is used in the traditional method, but the effect is bad in fog and other inclement weather. A re-mote sensing and computer vision positioning method of atmospheric laser communication based on the use of space is pro-posed. The atmosphere laser communication features are used. The wavelet edge detection method is used to extract the re-mote sensing image feature, and the human target positioning in mountain is realized. Simulation result shows that the new method can effectively extract the visual features of objects in remote sensing, and the location is accurate. It has good ap-plication value in mountain search and rescue.

  4. Moraine-dammed glacial lake changes during the recent 40 years in the Poiqu River Basin, Himalayas

    XiuJuan Zhang; ShiYin Liu; Li Liu


    Glacier retreat is not only a symbol of temperature and precipitation change, but a dominating factor of glacial lake changes in alpine regions, which are of wide concern for high risk of potential outburst floods. Of all types of glacial lakes, moraine-dammed lakes may be the most dangerous to local residents in mountain regions. Thus, we monitored the dy-namics of 12 moraine-dammed glacial lakes from 1974 to 2014 in the Poiqu River Basin of central west Himalayas, as well as their associated glaciers with a combination of remote sensing, topographic maps and digital elevation models (DEMs). Our results indicate that all monitored moraine-dammed glacial lakes have expanded by 7.46 km2 in total while the glaciers retreated by a total of 15.29 km2 correspondingly. Meteorological analysis indicates a warming and drying trend in the Nyalam region from 1974 to 2014, which accelerated glacier retreat and then augmented the supply of moraine-dammed glacial lakes from glacier melt. Lake volume and water depth changed from 1974 to 2014 which indicates that lakes Kangxico, Galongco, and Youmojanco have a high potential for outburst floods and in urgent need for continuous moni-toring or artificial excavation to release water due to the quick increase in water depths and storage capacities. Lakes Jialongco and Cirenmaco, with outburst floods in 1981 and 2002, have a high potential risk for outburst floods because of rapid lake growth and steep slope gradients surrounding them.

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

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


    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

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

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


    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.

  7. Identifying Oil Exploration Leads using Intergrated Remote Sensing and Seismic Data Analysis, Lake Sakakawea, Fort Berthold Indian Reservation, Willistion Basin

    Scott R. Reeves; Randal L. Billingsley


    The Fort Berthold Indian Reservation, inhabited by the Arikara, Mandan and Hidatsa Tribes (now united to form the Three Affiliated Tribes) covers a total area of 1530 mi{sup 2} (980,000 acres). The Reservation is located approximately 15 miles east of the depocenter of the Williston basin, and to the southeast of a major structural feature and petroleum producing province, the Nesson anticline. Several published studies document the widespread existence of mature source rocks, favorable reservoir/caprock combinations, and production throughout the Reservation and surrounding areas indicating high potential for undiscovered oil and gas resources. This technical assessment was performed to better define the oil exploration opportunity, and stimulate exploration and development activities for the benefit of the Tribes. The need for this assessment is underscored by the fact that, despite its considerable potential, there is currently no meaningful production on the Reservation, and only 2% of it is currently leased. Of particular interest (and the focus of this study) is the area under the Lake Sakakawea (formed as result of the Garrison Dam). This 'reservoir taking' area, which has never been drilled, encompasses an area of 150,000 acres, and represents the largest contiguous acreage block under control of the Tribes. Furthermore, these lands are Tribal (non-allotted), hence leasing requirements are relatively simple. The opportunity for exploration success insofar as identifying potential leads under the lake is high. According to the Bureau of Land Management, there have been 591 tests for oil and gas on or immediately adjacent to the Reservation, resulting in a total of 392 producing wells and 179 plugged and abandoned wells, for a success ratio of 69%. Based on statistical probability alone, the opportunity for success is high.

  8. Researches on Geochemical Characteristics of Mountain Karst Lake Water and Diurnal Variation of Carbon and Oxygen Isotopes——Case study of Yaochiba Lake, Jinfo Mountain, Chongqing%山地岩溶湖水地球化学与碳氧同位素特征及其昼夜变化研究——以重庆金佛山药池坝湖为例

    蒋先淑; 杨平恒; 王建力; 于正良; 沈蔚


    采用多参数水质分析仪,对重庆金佛山药池坝湖水的地球化学、碳氧同位素特征及其昼夜变化进行研究,结果表明:研究区湖水温度、pH值、溶解氧、电导率、δ13CDIC和δ18O等指标均表现出明显的昼夜变化规律,水温、pH值、溶解氧和δ13CDIC等指标白天升高,夜间降低,电导率白天降低,夜间升高,表明湖水溶解无机碳变化过程受到物理因素和生物作用的共同影响.山地岩溶湖泊地球化学指标与δ13CDIc对外界环境敏感,湖泊蒸发强烈,水体中溶解无机碳(DIC)滞留时间长,湖水与大气CO2交换程度高,使湖水δ13CDIC值偏正,接近平衡状态.湖水蒸发线斜率较小,截距较大,氢氧同位素组成主要受大气降水氧同位素组成、湖泊水-气界面蒸发过程中的同住素动力分馏效应和湖底水-岩氧同位素交换的影响.%Multi-parameter water quality analyzer on-line monitoring,artificial sampling,field titration and laboratory analysis methods were applied to investigate the geochemical,carbon isotopes,oxygen isotopes characteristics and the diurnal variation of those parameters in the lake,which located at Jinfo Mountain,Chongqing.Results showed that the lake temperature,pH,dissolved oxygen,conductivity and δ13CDIC suffered significantly diurnal variation.The lake water temperature,pH,dissolved oxygen and δ13CDIC indexes increased during the day and decreased during the night,which attribute to both physical and biological factors.It is found that the karst lake system is sensitive to environmental changes.In the research area,the lake has been evaporating strongly.The DIC can stay a long time in water.Meanwhile,the high extent of exchange between lake water and CO2 in the atmosphere resulted in positive value of δ13CDIC which reached to its equilibrium.The evaporation line of the lake was obtained,which had a lower slope and a higher intercept.Two main factors affected the isotopic composition of

  9. Remote estimation of chlorophyll-a concentration in turbid water using a spectral index: a case study in Taihu Lake, China

    Cheng, Chunmei; Wei, Yuchun; Lv, Guonian; Yuan, Zhaojie


    Chlorophyll-a concentration (Chla) is a key indicator of water quality, and accurate estimates of Chla using remote sensing data remain challenging in turbid waters. Previous research has demonstrated the feasibility of retrieving Chla in vegetation using spectral index, which may be the potential reference for Chla inversion in turbid waters. In this study, 106 hyperspectral indices, including vegetation, fluorescence, and trilateral indices, as well as combinations thereof, are calculated based on the in situ spectra data of 2004 to 2011 in Taihu Lake, China, to explore their potential use in turbid waters. The results show that the normal chlorophyll index (NCI) (R690/R550-R675/R700)/(R690/R550+R675/R700) is optimal for Chla estimation, with a determination coefficient (R) of 0.92 and a root mean square error (RMSE) of 14.36 mg/m3 for the data from July to August 2004, when Chla ranged from 7 to 192 mg/m3. Validation using the datasets of 2005, 2010, and 2011 shows that after reparameterization, the NCI model yields low RMSEs and is more robust than the three- and four-band algorithms. The results indicate that the NCI model can satisfactorily estimate Chla in multiple datasets without the need of additional band tuning.


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

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

    Metzger, Stephen M.


    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.

  12. Lake Ladora sampling plan, 1993

    US Fish and Wildlife Service, Department of the Interior — Task plan from the U.S. Geological Survey for sampling Lake Ladora on the Rocky Mountain National Wildlife Refuge. During the review of the FY93 Surface-Water...

  13. 91st Congress : 1st Session : S. 3014 [Hart Mountain NAR, Alaska Maritime NWR, Three Arch Rocks NWR, Oregon Islands NWR, Bitter Lake NWR, Malheur NWR

    US Fish and Wildlife Service, Department of the Interior — This document is a bill meant to designate certain lands in the Hart Mountain National Antelope Refuge, Alaska Maritime National Wildlife Refuge, Three Arch Rocks...

  14. Proposal for the pre-sediment removal aquatic survey of Lake Mary, Ladora, and Lower Derby Reservois located on the U.S. Army Rocky Mountain Arsenal, Colorado

    US Fish and Wildlife Service, Department of the Interior — Proposal for a monitoring program at the Rocky Mountain Arsenal (RMA) to document the effectiveness of the sediment removal program. This project has been initiated...

  15. 基于多星遥感影像的太湖北部湖湾春季沉水植被分布动态监测%Dynamic Monitoring of Distribution of Submerged Vegetation in the North of Taihu Lake in Spring Based on Multi-source Remote Sensing Images

    侍昊; 张婷; 李旭文; 牛志春; 王甜甜; 李杨


    The distribution and variation of submerged vegetation in the north of Taihu Lake in the spring of 2015 were monitored u-sing multi-source remote sensing images.This paper discussed the key problems in monitoring aquatic vegetation by using the tech -nique.The monitoring results acquired on 28th of April based on the decision tree method showed that the area of submerged vegeta -tion in the north of Taihu Lake was about 11.2 km 2 .Compared with the results obtained from the same period in 2014,the newly e-merged large areas of submerged vegetation were mainly concentrated near the west of Tianji Mountain and around of Xidong Water -works.It was suggested that submerged vegetation should be cleared away and salvaged timely to avoid the death and decay of aquat -ic vegetation,which posed threats to water quality .%利用多星遥感影像动态监测了2015年春季太湖北部湖湾沉水植被分布的变化过程,并对水生植被遥感监测中的几个关键问题展开了探讨。决策树方法获取的水生植被分布结果表明,2015年4月28日太湖北部湖湾发现明显沉水植被分布面积约11.2 km 2,与2014年同期相比,新出现的较大面积沉水植被分布区域主要集中在田鸡山西和锡东水厂附近。提出应及时清理打捞,避免水生植被死亡腐烂,威胁水质安全。

  16. Design and application of monitoring and early warning to Kyagar glacier lake in the Karakorum mountain%喀喇昆仑山克亚吉尔冰川湖监测预警设计与应用

    彭亮; 敖志刚; 陈建江; 姜卉芳


    针对喀喇昆仑山克亚吉尔冰川湖历史上发生多次溃决洪水问题,通过在克亚吉尔冰川湖区选点布设地面监测站,实时监测冰川湖图像、逐日气象、湖水位等7项气象水文要素数据,获得了克亚吉尔冰川湖区地面实测资料,直观地分析冰川湖是否形成及排泄,提前向叶尔羌河下游发出防洪预警警报。目前,冰川湖监测系统运行良好,各项技术指标均满足要求。%Pointed at the problem of Kyagar glacial lake outburst floods ( GLOF) occured frequently in the Karakoram Mountains,the paper installed the observation stations at the Kyagar Glacier Lake which can monitor the local meteorology data,the images and Water level of the Kyagar Glacier Lake,etc.It ana-lyzed the local climate data and images daily to know wether the Kyagar Glacier Lake forms and draina-ges.Thus,a flood warning can early alerts to Yarkant River flood plain.The monitoring system runs well and every technical indicator meets the requirement.

  17. Study on Greening Planning of Visual Mountain Surface of Fuxian Lake in Chengjiang%澄江县抚仙湖近面山绿化规划研究

    孔维琳; 王余舟; 彭明春; 王崇云; 马绍宾


    依据景观生态学的基本原理,提出澄江县抚仙湖近面山区域的生态景观设计与绿化规划方案:①对可视域区域原有的受损生态系统进行生态重建和生态修复;②对坡度25°以上旱地实施退耕还林,对坡度25°以下的山地进行生态优化和抚育;③对石灰山山地选用乡土树种抚育现状植被;④结合道路与景观的距离,对环湖公路、澄江至帽天山公路、澄江至阳宗公路和环湖岸绿化进行植物种类的优化配置;⑤对帽天山国家地质公园的矿山迹地开展生态修复、造林和植被抚育等.规划方案旨在促进区域生态旅游价值的提升和水环境保护.%According to the principles of the landscape ecology, landscape ecological design greening planning on visual mountain surface of Fuxian Lake in Chengjiang have been carried out as followed: 1) make ecological restoration for damaged ecosystems in sensitive zones of view-shed: 2) carry out sloping land conversion program on cropland with slope more than 25 °: and ecological optimize and tending on contrast: 3) select local tree species for lime mountain: 4) carry out roadside greening on the lake shore highway, roads of Chengjiang to Maotianshan, Chengjiang to Yangzong, as well as lake shore. Depending on visual distance from roads to landscape, tree species combination were optimized: 5 ) mining wasteland on Maotianshan mountain (close to the National Geopark) were planned for ecological restoration, afforestation, and vegetation regeneration. The planning will promote the local ecological tourism and water-body protection.

  18. Historical changes in the ecosystem condition of a small mountain lake over the past 60 years as revealed by plankton remains and Daphnia ephippial carapaces stored in lake sediments.

    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.

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

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


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

  20. A Study of Legislative Protection of Cangshan Mountain and Erhai Lake%苍山洱海立法保护经验的借鉴与启示

    李雪松; 孙大雄


    The successful experience of legislation to protect Cangshan Mountain and Erhai Lake, is worth learning and reference in other autonomous areas. For example, full use of legislative autonomy to develop protection regulations, develop supporting government regulatory documents, set up specific administrative bodies, moves towards timely amendments to regulations, preparation of ecological environmental protection in planning, and so on. The other hand, inadequate legislative protection of Cangshan Mountain and Erhai Lake also exists, where perfection is needed. For example, we should establish the purpose and basic principles of ecological protection legislation, adoption of legislation establishing ecological benefit compensation mechanism, and so on.%苍山洱海的立法保护,为民族自治地方的生态立法保护提供了一个成功的范例,当中有不少经验值得总结和借鉴。例如,充分利用立法自治权制定保护条例、制定配套的政府规范性文件、设立专门的行政执法机关、根据形势发展及时修订法规、编制地区生态环境保护规划等等。另一方面,苍山洱海的立法保护也有不足而需要完善的地方,比如应当确立生态保护立法的宗旨和基本原则,通过立法建立完善的生态利益补偿机制等等。

  1. Climate and Geomorphic Risks in High-Mountain Environments

    Huggel, Christian; Kääb, Andreas; Schneider, Jean


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

  2. Fluvial Process Influenced by Earthquake Lakes and Restoration of Mountain Rivers%地震堰塞湖对山区河流的影响与综合治理



    On 12 May 2008, a devastating mega-earthquake of magnitude 8.0 struck the Wenehuan area, north-western Sichuan province, China. Wenchuan earthquake inevitably impaired the stability of mountains in the course of massive reverse-thrust strike-slip motion in the fault zone. Geohazards were triggered with the types of rock fall, rock avalanches, landslides, debris flows, and earthquake-lakes. In this paper, the types and characteristics of dammed lakes induced by Wenchuan earthquake are analized. The dammed lakes would seriously influence the riv-er sediment transportation, fluvial processes and ecoenvironment. Consequently, the guidline and effective approa-ches for river restoration of dammed lake are susggested, so as to mitigate hazard loss and make the rivers influ-enced by the dammed lake serve us better.%2008年5月12日,中国四川汶川发生里氏8.0级地震,对四川和甘肃的13个县市造成了严重破坏.强烈的主震和余震在地震区造成了大量的滚石、崩塌、滑坡、泥石流、碎屑流等次生山地灾害,大规模滑坡崩塌堵断河道形成堰塞湖,引起山区河流强烈演变.分析了汶川"5·12"地震在四川省境内形成的众多堰塞湖(体)的不同类型、组成特征,提出堰塞体等河道堆积物对河流自然形态、生态环境和人类社会可能存在的影响.针对震后山区河流开发保护与生态环境建设的目标,对堰塞体综合治理提出了具体的指导意见和措施,以便尽可能地避害趋利,有效维护河流的健康.

  3. Spatio-temporal analysis of gyres in oriented lakes on the Arctic Coastal Plain of northern Alaska based on remotely sensed images

    Zhan, Shengan; Beck, Richard A.; Hinkel, Kenneth M.; Liu, Hongxing; Jones, Benjamin M.


    The formation of oriented thermokarst lakes on the Arctic Coastal Plain of northern Alaska has been the subject of debate for more than half a century. The striking elongation of the lakes perpendicular to the prevailing wind direction has led to the development of a preferred wind-generated gyre hypothesis, while other hypotheses include a combination of sun angle, topographic aspect, and/or antecedent conditions. A spatio-temporal analysis of oriented thermokarst lake gyres with recent (Landsat 8) and historical (Landsat 4, 5, 7 and ASTER) satellite imagery of the Arctic Coastal Plain of northern Alaska indicates that wind-generated gyres are both frequent and regionally extensive. Gyres are most common in lakes located near the Arctic coast after several days of sustained winds from a single direction, typically the northeast, and decrease in number landward with decreasing wind energy. This analysis indicates that the conditions necessary for the Carson and Hussey (1962) wind-generated gyre for oriented thermokarst lake formation are common temporally and regionally and correspond spatially with the geographic distribution of oriented lakes on the Arctic Coastal Plain. Given an increase in the ice-free season for lakes as well as strengthening of the wind regime, the frequency and distribution of lake gyres may increase. This increase has implications for changes in northern high latitude aquatic ecosystems, particularly if wind-generated gyres promote permafrost degradation and thermokarst lake expansion.

  4. Assimilation of Remotely Sensed Data into the Biome-BGC Ecosystem Model to Improve the Prediction of Energy and Carbon Exchange in Southwestern Mountain Island Forests

    Brown-Mitic, C. M.; Burke, E. J.; Shuttleworth, W. J.; Petti, J. R.; Harlow, R. C.; Brooks, P. D.


    Mountain island forest ecosystems populate high-altitude areas in the semi-arid southwestern U.S. and northwestern Mexico. In these regions, on average, the precipitation input exceeds the evapotranspiration loss. Therefore, they represent the primary source area for sustainable water resources, as well as making a major contribution to the regional carbon balance. During 2002 a 30-m tall micrometeorological tower was installed at a sky island forest site in the Santa Catalina Mountains, near Tucson AZ in order to characterize the surface exchanges of water, energy, and carbon. Measurements to date indicate that the surface fluxes are very sensitive to water status, for example, stomatal functioning totally closed down during the pre-monsoon period in 2002. Initial studies with the Biome Biogeochemical model (Biome-BGC) using driving data measured in the Santa Catalina Mountains provide reasonable simulations of the behavior of the mountain island forest. In order to obtain a regional estimate of the carbon exchange using a model such as Biome-BGC accurate estimates of the distributed forcing data particularly the precipitation are required. Alternatively, an estimate of the soil water status and the leaf area index can be used to improve model predictions. TERRA-MODIS leaf area index and fraction of photosynthetically active radiation (FPAR) are both sensitive to drought stress. Time periods during which there is a marked and sustained decrease in FPAR are shown to be symptomatic of a sustained period of low soil moisture that started 10-20 days earlier. Under these conditions the soil moisture status in Biome-BGC can be set to an arbitrary low value. Initial modeling studies demonstrate significant improvement in the prediction of surface exchange when using FPAR to diagnose periods of water stress.

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

    Qiang Zhu


    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.

  6. Methods for calculating glacier area and length in a mountainous area based on remote-sensing data and a digital elevation model


    In a mountainous region, the glacier area and length extracted form the satellite imagery data is the projected area and length of the land surface, which can’t be representative of the reality; there are always some errors. In this paper, the methods of calculating glacier area and length calculation were put forward based on satellite imagery data and a digital elevation model (DEM). The pure pixels and the mixed pixels were extracted based on the linear spectral un-mixing approach, the slop of the pixels was calculated based on the DEM, then the area calculation method was presented. The projection length was obtained from the satellite imagery data, and the elevation differences was calculated from the DEM. The length calculation method was presented based on the Pythagorean theorem. For a glacier in the study area of western Qilian Mountain, northwestern China, the projected area and length were 140.93 km2 and 30.82 km, respectively. This compares with the results calculated by the methods in this paper, which were 155.16 km2 and 32.11 km respectively, a relative error of the projected area and length extracted from the LandSat Thematic Mapper (TM) image directly reach to -9.2 percent and -4.0 percent, respectively. The calculation method is more in accord with the practicality and can provide reference for some other object’s area and length monitoring in a mountainous region.

  7. Automatic extraction of himalayan glacial lakes with remote sensing%喜马拉雅山地区冰湖信息的遥感自动化提取

    李均力; 盛永伟; 骆剑承


    在"全域-局部"分步迭代水体信息提取方法的基础上,通过对水体信息提取指标-水体指数的物理特性的分析实现了算法中全域阈值的自动选择与局部阈值的自适应调整,并结合DEM生成的山体坡度和阴影信息,减少局部迭代过程中对其他地表特征与水体信息的误判.在此基础上,建立一种适合于高山地区冰川湖泊的自动化提取方案.试验采用Landsat数据对喜马拉雅山地区的冰川湖泊进行信息提取,结果表明该方法能够快速准确地完成大区域范围内的冰川湖泊制图,并能最大程度地消除高山地区湖泊水体识别中冰川和山体阴影的影响.%The paper develops an automatic lake delineation algorithm based on "global-local" iterative scheme. The author uses NDWI (Normalized Difference Water Index) as the water identification index for the threshold segmentation process, and the slope maps and the shaded relief maps are applied in the algorithm to differentiate the shadow features from water features.Based on these methods. an automatic lakes delineation scheme is proposed to map the glacial lakes with Landsat Imagery in Himalayas mountains area. The results show that the proposed algorithm has good performance on lake mapping over the mountain areas, and lakes can be extracted automatically, accurately and efficiently, while most of melting glaciers and hill shadow features are eliminated from the segmentation processing.

  8. [Modeling of species distribution using topography and remote sensing data, with vascular plants of the Tukuringra Range low mountain belt (Zeya state Nature Reserve, Amur Region) as a case study].

    Dudov, S V


    On the basis of maximum entropy method embedded in MaxEnt software, the cartographic models are designed for spatial distribution of 63 species of vascular plants inhabiting low mountain belt of the Tukuringra Range. Initial data for modeling were actual points of a species occurrence, data on remote sensing (multispectral space snapshots by Landsat), and a digital topographic model. It is found out that the structure of factors contributing to the model is related to species ecological amplitude. The distribution of stenotopic species is determined, mainly, by the topography, which thermal and humidity conditions of habitats are associated with. To the models for eurytopic species, variables formed on the basis of remote sensing contribute significantly, those variables encompassing the parameters of the soil-vegetable cover. In course of the obtained models analyzing, three principal groups of species are revealed that have similar distribution pattern. Species of the first group are restricted in their distribution by the slopes of the. River Zeya and River Giluy gorges. Species of the second group are associated with the southern macroslope of the range and with southern slopes of large rivers' valleys. The third group incorporates those species that are distributed over the whole territory under study.

  9. Remote sensing analysis on lake area variations of Yamzho Yumco in Tibetan Plateau over the past 40 a%近40a西藏羊卓雍错湖泊面积变化遥感分析

    除多; 普穷; 拉巴卓玛; 朱立平; 张雪芹; 普布次仁; 德吉央宗; 孙瑞


    Lakes on the Tibetan Plateau play critical roles in the water cycle of the ecological and environmental systems of the Plateau. A better understanding of lake variations on the Tibetan Plateau is important for evaluating climate change and regional environment consequence under global warming. In this paper, as a typical inland lake and one of three holy lakes on the Tibetan Plateau , as well as a scenic spot in southern Tibetan Plateau, variations of Yamzho Yumco area from 1972 to 2010 and main factors controlling the variations are analyzed using remote sensing and CIS technologies in combination with climate data of meteorological stations within the basin. The results show that mean lake area is 643.98 km2 and mean perimeter is 709. 41 km from 1972 to 2010. The lake areas generally have been decreasing from 1972 to 2010. Specifically, the lake area in the 1970s was 658.78 km2 with the highest record of 678.42 km2 in 1972; the lake areas were 636.55 km2 and 635.06 km2 in the 1980s and 1990s, respectively. There is an increasing trend from 1999 to 2004. Hie year 2004 is a turning point for lake area variations, which is the end of increasing since 1999 and the starting point to decease until 2010. The lake areas have been significantly decreasing since 2004 with the mean annual decreasing rate(MADR) of8.59km2/a, which is higher than MADR of 6.85 km2 from 1972 to 1999. Especially, the smallest lake area, 600.26 km2, was recorded in 2010. The gap between the largest in 1972 and the smallest in 2010 for lake areas is 78.16 km2 with 11.52% of net areas in decease. The spatial variations of lake areas are characterized by the general shrinking trend from 1972 to 2010. Particularly, the shrinking distance reached 1. 62 km in eastern part of the lake with 42.63 m/a and 1.52 km in northwestern part of the lake with 40.00 m/a. The area variations of the lake are mainly caused by precipitation fluctuation and the increasing evaporation within the basin. Especially

  10. Towards an improved inventory of Glacial Lake Outburst Floods in the Himalayas

    Veh, Georg; Walz, Ariane; Korup, Oliver; Roessner, Sigrid


    The retreat of glaciers in the Himalayas and the associated release of meltwater have prompted the formation and growth of thousands of glacial lakes in the last decades. More than 2,200 of these lakes have developed in unconsolidated moraine material. These lakes can drain in a single event, producing potentially destructive glacial lake outburst floods (GLOFs). Only 44 GLOFs in the Himalayas have been documented in more detail since the 1930s, and evidence for a change, let alone an increase, in the frequency of these flood events remains elusive. The rare occurrence of GLOFs is counterintuitive to our hypothesis that an increasing amount of glacial lakes has to be consistent with a rising amount of outburst floods. Censoring bias affects the GLOF record, such that mostly larger floods with commensurate impact have been registered. Existing glacial lake inventories are also of limited help for the identification of GLOFs, as they were created in irregular time steps using different methodological approach and covering different regional extents. We discuss the key requirements for generating a more continuous, close to yearly time series of glacial lake evolution for the Himalayan mountain range using remote sensing data. To this end, we use sudden changes in glacial lake areas as the key diagnostic of dam breaks and outburst floods, employing the full archive of cloud-free Landsat data (L5, L7 and L8) from 1988 to 2015. SRTM and ALOS World 3D topographic data further improve the automatic detection of glacial lakes in an alpine landscape that is often difficult to access otherwise. Our workflow comprises expert-based classification of water bodies using thresholds and masks from different spectral indices and band ratios. A first evaluation of our mapping approach suggests that GLOFs reported during the study period could be tracked independently by a significant reduction of lake size between two subsequent Landsat scenes. This finding supports the feasibility

  11. Inroads of remote sensing into hydrologic science during the WRR era

    Lettenmaier, Dennis P.; Alsdorf, Doug; Dozier, Jeff; Huffman, George J.; Pan, Ming; Wood, Eric F.


    The first issue of WRR appeared eight years after the launch of Sputnik, but by WRR's 25th anniversary, only seven papers that used remote sensing had appeared. Over the journal's second 25 years, that changed remarkably, and remote sensing is now widely used in hydrology and other geophysical sciences. We attribute this evolution to production of data sets that scientists not well versed in remote sensing can use, and to educational initiatives like NASA's Earth System Science Fellowship program that has supported over a thousand scientists, many in hydrology. We review progress in remote sensing in hydrology from a water balance perspective. We argue that progress is primarily attributable to a creative use of existing and past satellite sensors to estimate such variables as evapotranspiration rates or water storage in lakes and reservoirs and to new and planned missions. Recent transforming technologies include the Gravity Recovery and Climate Experiment (GRACE), the European Soil Moisture and Ocean Salinity (SMOS) and U.S. Soil Moisture Active Passive (SMAP) missions, and the Global Precipitation Measurement (GPM) mission. Future missions include Surface Water and Ocean Topography (SWOT) to measure river discharge and lake, reservoir, and wetland storage. Measurement of some important hydrologic variables remains problematic: retrieval of snow water equivalent (SWE) from space remains elusive especially in mountain areas, even though snow cover extent is well observed, and was the topic of 4 of the first 5 remote sensing papers published in WRR. We argue that this area deserves more strategic thinking from the hydrology community.

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

    Anderson, Lesleigh; Max Berkelhammer,; Barron, John A.; Steinman, Byron A.; Finney, Bruce P.; Abbott, Mark B.


    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

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

    Anderson, Lesleigh; Berkelhammer, Max; Barron, John A.; Steinman, Byron A.; Finney, Bruce P.; Abbott, Mark B.


    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

  14. Late glacial aridity in southern Rocky Mountains

    Davis, O.K.; Pitblado, B.L. [Univ. of Arizona, Tucson, AZ (United States)


    While the slopes of the present-day Colorado Rocky Mountains are characterized by large stands of subalpine and montane conifers, the Rockies of the late glacial looked dramatically different. Specifically, pollen records suggest that during the late glacial, Artemisia and Gramineae predominated throughout the mountains of Colorado. At some point between 11,000 and 10,000 B.P., however, both Artemisia and grasses underwent a dramatic decline, which can be identified in virtually every pollen diagram produced for Colorado mountain sites, including Como Lake (Sangre de Cristo Mountains), Copley Lake and Splains; Gulch (near Crested Butte), Molas Lake (San Juan Mountains), and Redrock Lake (Boulder County). Moreover, the same pattern seems to hold for pollen spectra derived for areas adjacent to Colorado, including at sites in the Chuska Mountains of New Mexico and in eastern Wyoming. The implications of this consistent finding are compelling. The closest modem analogues to the Artemisia- and Gramineae-dominated late-glacial Colorado Rockies are found in the relatively arid northern Great Basin, which suggests that annual precipitation was much lower in the late-glacial southern Rocky Mountains than it was throughout the Holocene.

  15. The Tomb Statues beside Dongqian Lake



    Located 17 kilometers to the City of Ningbo, Dongqian Lake covers an area of 20 square kilometers, which is four only the biggest freshwater lake in Zhejiang Province but atso renowned for its gorgeous scenery. Recently, this beautiful lake once again caught people's eye because a large number of Southern Song Dynasty (1127-1279) gravestone statues were discovered among the mountains beside the lake area.

  16. Interesting Ziandao Lake


    LOCATED in Chun’an County, Zhejiang Province, Qiandao Lake (Lake of a Thousand Isles) is a state-level scenic spot and a bright pearl of the golden tourism line between Hangzhou’s West Lake and Anhui’s Huangshan Mountain. Last autumn, we went to Chun’an. It took only three to four hours by coach to travel from Hangzhou to Chun’an. Flanked by mountains on the west, the small county faces water on the east. A street goes across the county; it takes less than half an hour to walk from one end to the other. Small restaurants and shops line the western side of the road,

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

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


    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

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

    Mukesh Singh Boori


    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.

  19. Hazard Assessment of Glacial Lake Outburst Flood and Potential of ICTs for Coping: A Case of Eastern Himalaya of Nepal

    Bhattarai, D. R.


    Retreat of glaciers and formation of glacial lakes in Nepal Himalaya have been reported to be related with the temperature rise in the region. Glacier Lake Outburst Floods (GLOF) are the growing climate induced hazards in the Himalaya. GLOF has increased the vulnerability of community and fragile ecosystem in the mountain valleys. This study has analyzed the potential impacts from GLOF in the highland of eastern Nepal and the potential role of Information Communication Technologies (ICT) to cope with such impacts. I analyzed the trend of climatic pattern (temperature and precipitation) of the Eastern Himalaya Region of Nepal available from the Department of Hydrology and Meteorology, Government of Nepal, and prepared the latest location map of the glacial lakes using google earth and ArcGIS applications in the highland of the Kanchanjungha Conservation Area of the region. Tiptala glacial lake, located at an elevation of 4950 m, within the conservation area, was selected for the GLOF hazard assessment. I used semi-structured questionnaire survey and key informants' interviews in the community in order to assess the potential hazard of GLOF. With the varying sizes, 46 glacial lakes were located in the region, which covers over 2.57 sq. km in total. Though the larger portion of the downstream area of the Tiptala glacial lake fall in the remote location away from major residential area, few villages, major pasture lands for Yaks, foot trails, and several bridges across the Tamor River below the lake are in risk of GLOF. Poor access due to extreme geographical remoteness and capacity to afford the modern technologies in the community are the major limiting factor to the knowledge and information about the climate change and related impacts. Modern ICTs has high potential to reduce the risk of climate related hazards in the remote area by information dissemination and awareness.

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

    Darko Ogrin


    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.

  1. Lakes: recent research and restoration strategies

    Karen L. Pope; Jonathan W. Long


    The Sierra Nevada and southern Cascade Range support thousands of montane lakes, from small, remote tarns to iconic destinations such as Lake Tahoe. Their beauty and recreational opportunities instill high social value, in particular by serving as destinations for hiking, camping, swimming, and fishing. Lakes also have high ecological value because they support a...

  2. 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.

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


    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.

  3. Research on remote sensing image segmentation based on ant colony algorithm: take the land cover classification of middle Qinling Mountains for example

    Mei, Xin; Wang, Qian; Wang, Quanfang; Lin, Wenfang


    Remote sensing image based on the complexity of the background features, has a wealth of spatial information, how to extract huge amounts of data in the region of interest is a serious problem. Image segmentation refers to certain provisions in accordance with the characteristics of the image into different regions, and it is the key of remote sensing image recognition and information extraction. Reasonably fast image segmentation algorithm is the base of image processing; traditional segmentation methods have a lot of the limitations. Traditional threshold segmentation method in essence is an ergodic process, the low efficiency impacts on its application. The ant colony algorithm is a populationbased evolutionary algorithm heuristic biomimetic, since proposed, it has been successfully applied to the TSP, job-shop scheduling problem, network routing problem, vehicle routing problem, as well as other cluster analysis. Ant colony optimization algorithm is a fast heuristic optimization algorithm, easily integrates with other methods, and it is robust. Improved ant colony algorithm can greatly enhance the speed of image segmentation, while reducing the noise on the image. The research background of this paper is land cover classification experiments according to the SPOT images of Qinling area. The image segmentation based on ant colony algorithm is carried out and compared with traditional methods. Experimental results show that improved the ant colony algorithm can quickly and accurately segment target, and it is an effective method of image segmentation, it also has laid a good foundation of image classification for the follow-up work.

  4. 天山北坡草地遥感分类及其精度分析%Typical grassland classification and precision evaluation based on remote sensing data in the northern slope of Tianshan Mountain

    周伟; 杨峰; 钱育蓉; 李建龙


    基于遥感资料的植被类型划分能快速获得大尺度的植被覆盖变化数据。采用遥感和GIS技术,利用天山北坡典型草地2008年Landsat 5-TM遥感影像和1999年Landsat 7-ETM+全色波段数据,在对遥感影像预处理的基础上,进行了数据融合处理。根据融合影像的纹理特征进行监督分类,将研究区域的植被初步分为8种主要覆盖类型,在监督分类的基础上借助专家知识系统构建决策树,进一步将草地分为5类,包括平原荒漠、平原沙漠、低山荒漠、温性草甸和高寒草甸,最后对分类结果进行精度评价,总精度在95%以上,总Kappa系数为0.939 6,间隔9年的影像融合和决策树分类方法在研究区植被分类中具有较高的可行性。%Vegetation classification based on remote sensing data can quickly get vegetation change information at large scale.This paper chose the Landsat TM data in 2008 and Landsat ETM+ Pan data in 1999 of the typical grassland in the northern slope of Tianshan Mountain.The data used in this paper were pre-processed firstly,then the two temporal remote sensing data were fused by means of remote sensing and GIS(Geographic Information System) technologies.The vegetation in the study area was classified into eight types by visual interpretation based on the texture feature of the fused remote sensing image.Besides,we established an expert knowledge decision tree system to make a further classification combining the preliminary classification results of the visual interpretation.At last the grasslands in the study area were classified into five types,including plain desert,desert plants,low-mountain desert,temperate meadow and alpine meadow.The results of accuracy evaluation indicated that the overall classification accuracy reaches to 95%,and the overall Kappa coefficient is 0.9396,which suggests that the vegetation classification methods based on the fused image generated by nine-year interval TM and ETM+ Pan images

  5. 自走式山地单轨运输机遥控系统的设计%Design of the remote control system for self-propelled mountainous monorail transporter

    张俊峰; 张衍林; 张唐娟; 李善军; 孟亮


    In order to reduce labor intensity and ensure safe operation a remote control system based on MCU AT89S52 was designed by using the self-propelled monorail transporter 7YGD-35 as the research object. The system is composed of the remote controller, the central processing unit and the electromotive handspike, etc. The clutch actuator, shift actuator, throttle actuator and brake actuator are designed to make accurate control, which all use the electromotive handspike as the core. The experimental results show that the control distance is as far as 300 m, and it is perfectly suitable for the transportation of mountainous citrus orchard. Therefore, there is a good prospect for the application of the system for monorail transporter.%为降低劳动强度和保证安全作业,以7YGD-35型自走式单轨运输机为研究对象,设计了一套基于AT89S52单片机的遥控系统.该控制系统主要由遥控器、中央处理单元和电动推杆等组成,以电动推杆为核心设计了离合执行机构、换挡执行机构、油门执行机构和制动执行机构,实现对自走式单轨运输机的离合、换挡、油门、制动等准确控制.田间实地作业试验结果表明,该控制系统遥控距离可达300 m,适合山地橘园运输作业,具有良好的应用前景.

  6. Habitat improvement plan for Lower Derby Lake

    US Fish and Wildlife Service, Department of the Interior — Rocky Mountain Arsenal National Wildlife Refuge (RMANWR) is home to several species of both aquatic and terrestrial wildlife. Within the three Refuge lakes, Mary,...

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

    Nabil Sayed Embabi


    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.

  8. [Evaluation on the atmospheric correction methods for water color remote sensing by using HJ-1A/1B CCD image-taking Poyang Lake in China as a case].

    Zeng, Qun; Zhao, Yue; Tian, Li-Qiao; Chen, Xiao-Ling


    HJ-1A/1B satellite CCD images have higher spatial and temporal resolution, making them of great potential in quantitatively monitoring the water quality of inland lakes. However, the atmospheric correction of the images restricts their application. Therefore, taking Poyang Lake, the biggest freshwater lake in China as study area , and using the in-situ data collected in 2009 and 2011, this paper compares the atmospheric correction results done by the four methods: FLAASH, 6S, COST and QUAC, and analyzes the influence of these atmospheric correction methods on the inversion accuracy of the total suspended sediments (TSS) concentration. The results indicate: (1) the band 1 (blue band) of HJ-1A/1B CCD satellite images should be recalibrated while being applied into water quality remote sensing. The accuracy of atmospheric correction done from band 2 (green band) and band 3 (red band) is higher than that of others , especially that of the correction done by FLAASH, 6S and COST is much higher while that of correction done by QUAC is lower. So the algorithms of QUAC should be pointedly improved. (2) The ratios done from band 2 and band 3 have a good match with in-situ data , with an average relative error of 8.2%, 9.5%, 7.6% and 11.6% respectively for FLAASH, 6S, COST and QUAC. Therefore, it would be better to use the ratio done from band 2 and band 3 as inversion factors in Poyang Lake. (3) It is found that the accuracy of directly building models by using the four atmospheric corrected results and the TSS concentration is higher than the models built by the in-situ remote sensing reflectance and the TSS concentration. The accuracy of the TSS concentration inverted by FLAASH, 6S and COST is much high with an average error of only 10.0%, 10.2% and 8.0% respectively, while the error inverted by QUAC is a little bit higher of being 18.6%. So it is suggested to build model with atmospheric correction results and the TSS concentration data, because it can avoid the cumulate

  9. Development of Hyperspectral Remote Sensing Capability For the Early Detection and Monitoring of Harmful Algal Blooms (HABs) in the Great Lakes

    Lekki, John; Anderson, Robert; Nguyen, Quang-Viet; Demers, James; Leshkevich, George; Flatico, Joseph; Kojima, Jun


    Hyperspectral imagers have significant capability for detecting and classifying waterborne constituents. One particularly appropriate application of such instruments in the Great Lakes is to detect and monitor the development of potentially Harmful Algal Blooms (HABs). Two generations of small hyperspectral imagers have been built and tested for aircraft based monitoring of harmful algal blooms. In this paper a discussion of the two instruments as well as field studies conducted using these instruments will be presented. During the second field study, in situ reflectance data was obtained from the Research Vessel Lake Guardian in conjunction with reflectance data obtained with the hyperspectral imager from overflights of the same locations. A comparison of these two data sets shows that the airborne hyperspectral imager closely matches measurements obtained from instruments on the lake surface and thus positively supports its utilization for detecting and monitoring HABs.

  10. 浅谈偏远山区小学信息技术教育的发展现状%On the Development Situation of Information Technology Education in Remote Mountainous Primary Schools



    教育没有绝对的平等,教育水平同教学设施、师资力量、地域差异、城乡差异息息相关。作为山区小学信息技术教育工作者,笔者认为信息技术教育发展滞后的根本原因为:教学设备不足、课程重视不够、师资力量薄弱、信息交流闭塞、远程教育不够发达。%There is no absolute equality of education,the teaching facilities,teacher strength,regional differences,the differences between urban and rural areas are closely related.As a mountainous area primary school information technology education workers,see information technology education lags behind the development of underlying causes,namely:the church and inadequate equipment,courses seriously insufficient,weak teachers strength,the exchange of information occlusion,remote education development.

  11. Response of ice cover on shallow lakes of the North Slope of Alaska to contemporary climate conditions (1950–2011: radar remote sensing and numerical modeling data analysis

    C. M. Surdu


    Full Text Available Air temperature and winter precipitation changes over the last five decades have impacted the timing, duration, and thickness of the ice cover on Arctic lakes as shown by recent studies. In the case of shallow tundra lakes, many of which are less than 3 m deep, warmer climate conditions could result in thinner ice covers and consequently, to a smaller fraction of lakes freezing to their bed in winter. However, these changes have not yet been comprehensively documented. The analysis of a 20 yr time series of ERS-1/2 synthetic aperture radar (SAR data and a numerical lake ice model were employed to determine the response of ice cover (thickness, freezing to the bed, and phenology on shallow lakes of the North Slope of Alaska (NSA to climate conditions over the last six decades. Analysis of available SAR data from 1991–2011, from a sub-region of the NSA near Barrow, shows a reduction in the fraction of lakes that freeze to the bed in late winter. This finding is in good agreement with the decrease in ice thickness simulated with the Canadian Lake Ice Model (CLIMo, a lower fraction of lakes frozen to the bed corresponding to a thinner ice cover. Observed changes of the ice cover show a trend toward increasing floating ice fractions from 1991 to 2011, with the greatest change occurring in April, when the grounded ice fraction declined by 22% (α = 0.01. Model results indicate a trend toward thinner ice covers by 18–22 cm (no-snow and 53% snow depth scenarios, α = 0.01 during the 1991–2011 period and by 21–38 cm (α = 0.001 from 1950–2011. The longer trend analysis (1950–2011 also shows a decrease in the ice cover duration by ∼24 days consequent to later freeze-up dates by 5.9 days (α = 0.1 and earlier break-up dates by 17.7–18.6 days (α = 0.001.

  12. Survey of linear structural features from remote sensing – a contribution to the geotechnical mapping in Baturité Mountain, Ceará

    Clístenes Teixeira Batista


    Full Text Available The use of techniques of digital image processing remote sensing allows applications of great importance for the geosciences. One of the possible fields of application of these resources is the geotechnical mapping. Filtering techniques for radar and optical images emphasize natural linear structures that can be interpreted as fractures, drainages, ridges, valley bottoms and foliation. With the lifting of these data, combined with field work, the geotechnical mapping gains in precision and agility. The high incidence of slope instability events recently occurred in some parts of Brazil, especially in the Southeast, has attracted the interest of researchers in engineering and geoscience areas in the preparation of monographs, dissertations, theses and academic articles that address this issue. For subsequent generation of a diagram rosettes and visualization of regional trend of the structures and preparation of lineament density map, the vectors corresponding to the guidelines direction were measured in azimuth, and the length was measured in meters. The importance of applying frequency spectrum filters is therefore to quantify and qualify these geological and geomorphological structures, which are among the main components of conditions of mass movements and erosion.

  13. Evidence for endocrine disruption in perch (Perca fluviatilis) and roach (Rutilus rutilus) in a remote Swedish lake in the vicinity of a public refuse dump

    Noaksson, E.; Tjärnlund, U.; Bosveld, A.T.C.; Balk, L.


    A two-year study on perch (Perca fluviatilis) in Lake Molnbyggen, Sweden, located in a pristine area but with a public refuse dump in the vicinity, has been conducted. The mechanistic approach through a set of biomarkers during the first year included age, condition, somatic growth, liver, gonad, an

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

    Krupa Elena G.


    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

  15. Assessing the feasibility of integrating remote sensing and in-situ measurements in monitoring water quality status of Lake Chivero, Zimbabwe

    Dlamini, S.; Nhapi, I.; Gumindoga, W.; Nhiwatiwa, T.; Dube, T.


    This work investigates the likelihood of integrating the cheap and readily-available broadband multispectral MODIS data and in-situ measurements in quantifying and monitoring water quality status of an inland lake within Upper Manyame Catchment in Zimbabwe. Specifically we used MODIS images to quantify inland lake chlorophyll_a concentrations, as a proxy for predicting lake pollution levels. The findings of this study show a high chlorophyll_a concentration of 0.101 ± 0.128 μg/L within the Lake. The results further demonstrated that the chlorophyll_a concentration levels did not significantly vary (p = 0.788) between sites, except among depths (p = 0.05). Further, prediction results based on the relationship between observed and predicted chlorophyll_a produced a high R2 value of 0.89 and a root mean square error (RMSE) value of 0.003 μg/L. Moreover, the derived landuse maps of Upper Manyame Catchment indicated a significant variation in the percentage settlement in 1985, 1994 and 2010 change from 1985 to 2010. For instance, 8% increase in settlement in the period between 1994 and 2010 and over 12% increase from 1985 to 2010 and a decline in percent forest coverage (i.e. 9.8% in 1985 to 2.0% in the year 2010) in the catchment was observed. Overall, the findings of this study highlights the importance of free and readily-available satellite datasets (such as the multispectral MODIS and Landsat) in quantifying and monitoring water quality across inland lakes especially in data-scarce areas like Sub-Saharan Africa.

  16. Calculating Lake Morphology in the Colville River Delta, Alaska

    McGraw, M.; Walker, H. J.


    The morphology and surface area of a lake can be determined using simple mathematical formulas. These formulas can be plugged into a Geographic Information System (GIS) and used to calculate the circularity, smoothness, compactness and orientation of a lake or pond in remotely sensed imagery. The calculated output can then be used to differentiate circular lakes from elongated lakes, lakes with smooth shorelines from those with complex shorelines, and lake orientation; such information can then be used to classify and quantify different types of lakes in complex environments such as river deltas. The Colville River delta is located on the North Slope of Arctic Alaska. Previous studies have classified the delta's 230,000+ lakes into five types: 1. thermokarst (thaw) lakes, 2. oriented lakes, 3. perched lakes, 4 channel lakes and 5. ice-wedge polygon ponds. This study uses 2004 aerial photography and 2011 satellite imagery to quantify the different types of lake in the delta.

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

    Chirinos, L. [Centro de Ciencias Ambientales EULA-Chile, Universidad de Concepcion, PO Box 160-C, Concepcion (Chile)]. E-mail:; 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)


    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.

  18. 滇池水体中总悬浮物含量的遥感定量模型%Remote sensing quality model of SS(suspended solid)in the dianchi lake water bodies

    赵碧云; 贺彬; 朱云燕; 袁国林


    Using synchronous monitoring data and TM data of la ndsat 5 , TMimage remote sencing Suspended Solid(SS) water quality model is established by corre lative degree analysis between Suspended Solid concentration and data of differe nt TM bands. The model successfully applied to remote sensing dynamic monitorin g of Suspended Solid in the Dianchi Lake water bodies.%利用滇池1999年4月14日陆地卫星TM数据与准同步全湖面监测资料,对滇池全湖水体总悬浮物含量与不同波段遥感值的关系进行了关联度分析,并据此建立了TM图像遥感总悬浮物水质模型,该模型被成功地应用于滇池水体总悬浮物的遥感动态监测。

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

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


    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.

  20. Relationship between environmental remote sensing alternate indexes and Oncomelania snail distribution in hilly and mountainous areas%环境遥感替代指标与山丘地区钉螺分布的关系

    董毅; 李朝晖; 冯锡光; 董兴齐


    Objective To analyze the relationship between Oncomelania snail distribution and environmental remote sensing indexes in hilly and mountainous areas. Method The normalized different vegetation index (NDVI), land surface temperature (LST), humidity index (Wetness) of 85 snail spots in Dali City were extracted for statistical analysis by TM image, and the land-use types were classified. LST, NDVI, Wetness, snail density and land-use types were overlaid and analyzed by using a weight of suitability model of ArcGIS 9.2, and snail appropriate distribution range in Dali City was calculated. Results The distribution of LST, NDVI, Wetness values of the investigated snail points were approximately normal, and most of the snail points distributed nearby the average values of the remote sensing alternate indexes, then gradually reduced to the ends. More than 90% of the snail spots were distributed in the land type with crops and grassland. The environments in Dali City were divided into unsuitable snail environment (0-14 points), suitable snail environment (15-21 points), and optimum snail environment (22-26 points) by the weight suitability mode. Conclusions Environmental remote sensing indicators can reflect the environmental factors affecting snail distribution directly. Combining remote sensing with GIS and field survey can describe, judge and forecast the distribution of snails.%目的 探讨影响山丘地区钉螺分布的常用环境遥感指标.方法 使用TM遥感图像提取云南省大理市85个螺点的植被指数(NDVI)、地表温度(LST)和湿度指数(Wetness)并进行统计分析,同时进行土地利用的分类;利用ArcGIS 9.2的权重适宜性模型将LST、NDVI、Wetness、钉螺密度、土地利用类型赋值后叠加分析,并计算大理市钉螺适宜分布范围.结果 提取的LST、NDVI、Wetness值均呈近似正态分布,螺点大部分分布在各遥感替代指标均数附近,并向两端逐渐减少,90%以上的螺点分布在代表庄

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

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


    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.

  2. Mountain saved. is a mountain earned

    Margolis, K.

    The Anaconda Copper Company boasted that the smokestack on its Washee smelter mill was the world's tallest. It also was probably the world's deadliest. Mysterious livestock deaths began occurring in 1906. They seemed to concentrate in the path of the prevailing westerly winds, carrying the Washee's smelter smoke plume toward Mt. Haggin. As evidence mounted that the deaths were connected to particulate fallout from the smelter (largely oxides of zinc, arsenic, lead, and copper), there were rumblings of lawsuits against Anaconda. The company felt threatened, but did not possess the technology to cure the situation. To protect itself, Anaconda purchased all the lands that were affected by fallout from the smelter smokestack. The result was the formation of the 154,000-acre Mt. Haggin Ranch. Today, the Anaconda Copper Company uses sophisticated pollution abatement equipment, and it is possible to see the healing that has taken place in recent years. The ranch includes rugged mountain peaks and ridges, high mountain valleys, and rolling foothills. A fisherman's paradise, the area also contains 20 mountain lakes, numerous ponds, and over 60 miles of trout streams. The Conservancy has been working to save Mt. Haggin since 1969. Negotiations have involved not only the fee owner--Mt. Haggin Livestock, Inc.--but also parties holding grazing and timber contracts, a variety of public agencies, and the Anaconda Company, which still holds some rights over the portion of the property not yet purchased by the Conservancy. The Conservancy assists in preserving lands like Mt. Haggin by handling the financial and legal aspects of land purchases. The Conservancy is allocating property to two ultimate recipients: the U.S. Forest Service and the montana Department of Fish and Game.

  3. Appendix A: Fuelwood availability for a ten megawatt power plant in Tupper Lake, New York, based on remotely sensed and other data


    Forested land potentially available for fuelwood harvest within 30 km of Tupper Lake, N.Y. was delineated and classified as to forest using NASA aerial photography and LANDSAT imagery. Published inventory and growth data were used to estimate woody material on the available land. The information submitted to the Energy Office indicates that there is sufficient woody material to supply a 10 MW plant.

  4. Analysis on death situation and causes of severe mental in remote mountainous areas%边远山区严重精神障碍患者三年死亡现状及原因分析

    张腾; 王晖; 李明松; 杨家芳; 郑维斌


    [目的]分析边远山区严重精神障碍患者3年死亡现状及原因,为保山市提高该类患者社区居家生存质量提供科学依据。[方法]收集保山市社区2011-2013年内266例死亡的严重精神障碍患者信息和死亡原因,结合国家重性精神疾病基本数据收集分析系统进行统计学分析。[结果]2011-2013年,保山市共死亡严重精神障碍患者266例,3年平均死亡率13.8‰,2012年死亡率最高(为17.3‰),60岁及以上、离婚、文盲患者死亡率最高(分别为31.6‰、33.0‰和17.5‰);躯体疾病死亡率最高(9.8‰),具体死因中脑出血最高(为3.2‰);不同性别、年龄、民族、文化程度、婚姻状况的患者死亡状况不同。[结论]边远山区严重精神障碍患者死亡率(13.8‰)较普通人群高(6.7‰),以躯体疾病、自杀及意外为主要死亡原因,应加强社区对患者的管理、护理措施,提高该类患者生存质量。%Objective To provide scientific basis for improving life quality through analyzing death situation and causes in three years of severe mental in remote mountainous areas.Methods Collected 266 cases information death causes of severe mental from 2011 to 2013 in Baoshan. Statistic analysis combined with national severe mental basic data. Results From 2011 to 2013, 266 severe mental was died, 3-years average mortality rate was 13.8‰, the highest of mortality rate was in 2012. The highest of mortality rate in aged 60 above or divorced or illiterate patients( 31.6‰、33.0‰、17.5‰).The mortality rate of physical illness was highest to 9.8‰, 3.2‰ was died in hematencephaion. The death status was different in different sex, age, nationality, education and marital status. Conclusions The mortality rate of severe mental(13.8‰) was higher than normal population(6.7‰) in remote mountainous areas. Main death causes was physical illness, suicide and accidents. So we must

  5. 山区地形对被动微波遥感影响的研究进展%Advances in the Study of Mountainous Relief Effects on Passive Microwave Remote Sensing

    李欣欣; 张立新; 蒋玲梅


    随着土壤湿度与海水盐度卫星( SMOS)发射计划的顺利开展和AMSR -E(Advanced Microwave Scanning Radiometer- Earth Observing System)业务化运行服务之后,人类用星载微波辐射计监测土壤水分是空间技术上的又一次飞跃,但土壤水分的反演精度受到微波辐射计低空间分辨率观测像元的空间异质性和地形的影响,尤其山区地形对大尺度被动微波遥感观测影响显著,其中包括微波辐射的传输路径受海拔高度的影响,地表发射特性受地形坡度和坡向的影响,山体间的多次反射和地形的阴影效应也会改变地表的散射特性.目前,数项微波辐射地形效应的模拟研究已在国内外开展,并据此提出了一些简化的地形校正方法.为了使人们对该领域研究有一概括了解,基于电磁波辐射传输的物理机理和地表形态特征的统计分析,首先探讨了地形效应对微波辐射传输和地表微波辐射特征以及土壤水分反演算法的影响,然后通过地形在微波辐射研究中的最新进展综述,提出了目前研究中存在的问题以及进一步的研究方向.%As SMOS (Soil Moisture and Ocean Salinity) mission has been carried out smoothly, and AMSR - E ( Advanced Microwave Scanning Radiometer - Earth Observing System) services have been conducted, people have achieved another great leap forward in monitoring surface soil moisture by satellite - borne microwave radiometer in space technology. Since space resolution is coarse under satellite microwave radiometer, the accuracy of retrieving soil moisture has been conditioned by space heterogeneity and relief effects. Mountainous terrain on a larger scale than wavelength has such significant effects on passive remote sensing as altitude role in microwave transmission path, topographic slope angle and aspect effects on surface emissivity, and multi - reflection between mountains or shadow effect on the change in surface scatter characteristics. A

  6. Mountaineering Tourism

    Patrick Maher


    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.

  7. Map showing areas with potential for talc deposits in the Gravelly, Greenhorn, and Ruby ranges and the Henrys Lake Mountains of southwestern Montana

    Van Gosen, Bradley S.; Berg, Richard B.; Hammarstrom, Jane M.


    For the last several years, Montana has been the leading talc producing state in the United States (U.S. Geological Survey, 1996). For example, in 1992 Montana supplied about 40 percent of the U.S. mine production of talc (Virta, 1992). All of this production has come from the large deposits of high purity talc in the southwestern part of the state. All Montana talc is currently (1997) extracted from four mines, each within the study area of this map—the open pit operations of the Treasure State, Regal, and Yellowstone mines and the underground operation of the Beaverhead mine (see map numbers 1-4 on list and map to the left). The related mineral chlorite is mined at the Antler mine, located nearby, but outside of the study area in the Highland Mountains. Montana talc has at least two market advantages: (1) some deposits are very large and near surface, allowing economic mining by open pit methods; and (2) the deposits are of high purity and lack tremolite or other amphibole mineral contaminants (such as absestos) that occur in some other talc-rich deposits. Talc from southwest Montana is used in ceramics, paint, paper, plastics, cosmetics, rubber, roofing, flooring, caulking, and agricultural applications. The talc is also used in the processes of recycling paper and plastics. Talc was first discovered in the early 1900's at the present site of the Yellowstone mine (Perry, 1948, p. 9). Modest production began in 1942 from shallow pits and adits, supplying steatite (massive, compact, high-purity) talc that was used to make ceramic insulators. The southwest Montana talc industry grew to become a significant part of the region's economy; this history is described by Perry (1948), Olson (1976), and Berg (1997). Exploration and development are likely to continue for the foreseeable future for several reasons: (1) mines are active in the area at present and an infrastructure for talc processing exists; (2) large changes in domestic and export talc markets are not

  8. Analysis of wind field features causing cyanobacteria bloom in Taihu Lake combined with remote sensing methods%结合卫星遥感技术的太湖蓝藻水华形成风场特征

    李亚春; 谢小萍; 杭鑫; 朱小莉; 黄珊; 景元书


    On the basis of the meteorological observation data and remote sensing data over the Taihu Lake and its surrounding areas during 2003 to 2013, combined with the WRF3.5.1 simulations, the relationships between the cyanobacteria blooms in Taihu Lake and surface wind speeds were analyzed. The results show that cyanobacteria blooms mainly occurred in the period of the weak wind speed about 0.5~3.4m/s, about six hours earlier than the MODIS satellite overpass time in Taihu Lake, which accounts for 94.7% of all cyanobacteria blooms events. As the area of cyanobacteria blooms decreasing with the wind speed strengthening, a large bloom of cyanobacteria bloom mainly occurred 6 hours ahead with the average wind speed less than 2m/s, accounting for 89%. In addition, the wind direction mainly affects the spatial patterns of cyanobacteria blooms in Taihu Lake. All these results suggest that the wind patterns play an important role on the formation, drifting and distribution of cyanobacteria blooms.%为进一步了解太湖蓝藻水华形成和分布与近地面风场的关系,利用太湖湖面及周边地区2003~2013年气象与卫星观测数据分析、并应用WRF3.5.1数值模型模拟,发现太湖蓝藻水华主要出现在卫星观测时刻前6h平均风速为0.5~3.4m/s的区间,占比达94.7%;蓝藻水华面积总体上随风速增大而减小,大范围蓝藻水华主要出现在前6h平均风速≤2m/s的情形下,占比达89%;风向则主要影响蓝藻水华在太湖的空间分布格局.结果表明局地风场对于太湖蓝藻水华的形成、输移和分布具有重要作用.

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

    C. Huggel


    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.

  10. Survival of Oncomelania Snails from Lake Regions and Mountain Regions and Their Susceptibility to Schistosoma Japonicum under Simulated Field Conditions%模拟自然条件下湖沼型和山区型钉螺存活率及其血吸虫易感性研究

    龚珍强; 李传昌; 汪雁; 黄重峰; 刘大仁; 陶波; 周宪民; 邹节新


    Objective To compare the 4-month survive rates of ribbed shell Oncomelania snails from lake regions of Xingzi County of Jiangxi Province,ribbed shell Oncomelania snails from mountain regions of Yushan County of Jiangxi Province and smooth shell Oncomelania snails from mountain regions of Pengshan County of Sichuan Province and their susceptibility to Schis-tosoma japonicum under simulated natural conditions.Methods Lake-region ribbed shell On-comelania snails,mountain-region ribbed shell Oncomelania snails and mountain-region smooth shell Oncomelania snails were collected from Xingzi County of Jiangxi Province,Yushan County of Jiangxi Province and Pengshan County of Sichuan Province,respectively.The infected and un-infected snails were screened using the cercariae escaping method.The Schistosoma japonicum-in-fected snails from Xingzi County were used to infect a rabbit.The liver was removed and miracidia were obtained after 45 days.Then snails were infected with the miracidia at a ratio of 120 at 26-30 ℃ under fluorescent lamp irradiation.These infected snails were fed for 4 months in Schistoso-miasis Control Station of Xingzi County under simulated natural conditions,and the survival rate and infection rate were determined.Results Oncomelania snails from mountain regions of Yushan County of Jiangxi Province and mountain regions of Pengshan County of Sichuan Province could survive under simulated natural conditions in Xingzi County of Jiangxi Province.But their survival rates were significantly lower than those from lake regions of Xingzi County of Jiangxi Province (P < 0.001 ).Furthermore,Oncomelania snails from lake regions of Xingzi County of Jiangxi Province and mountain regions of Yushan County of Jiangxi Province,but not those from moun-tain regions of Pengshan County of Sichuan Province,were easily infected with Schistosoma ja-ponicum miracidia from Xingzi County of Jiangxi Province.In addition,the infection rate of snails from lake regions of Xingzi

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

    Hook, Simon J.


    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.

  12. Successful Female Mountaineers



    The Third Mountaineering Meet took place from September 26 to October 8, 2003. It was sponsored by the Tibet Association for Mountaineers and undertaken by the Tibet Mountaineering Team and the Tibet Mountaineering School.

  13. The Deterioration of Ecology Environment and Its Cause in the Lake Regions of the Yellow River Source, Qinghai, China%黄河源区生态环境恶化的现状及其原因

    郑本兴; 唐邦兴; 李成治


    黄河是中华民族的母亲河,黄河流域是世界上著名的四大文明古国的发祥地之一。远古时代黄河流域气候湿润、水源丰富、土地肥沃。轩猿黄帝和他的沿黄部落就在这里开始创造中华文明。而今黄河下游常年发生断流,中游水土流失严重,河源区生态环境恶化,已引起我国政府和民众的关注。目前,防治黄河源区生态环境进一步恶化的研究工作必须加大力度,在财力、人力方面应给予更大的支持,及早编制该区治理生态环境的规划,加强环境保护措施。%The Yellow River is the mother river of the Chinese nation, andthe watersheds of the Yellow River is also one of four famous countries with an ancient civilization in the World. In remote antiquity, the climate was warm and moist, abundant water resources and good soil favorite to the Xuanyuan Emporia and his tribe lived along both sides of the Yellow River, and created a Chinese civilization. But at present a broken flow of the Yellow River is frequent in the lower reach and heavy soil erosion in the middle reach, ecological environment steadily deteriorated in the headwater. Attention has be paid to these situations by the chinese Government and their people.Over the confluence of the Maqu River and Heihe River (the range before the Huashixia)is called the source region of the Yellow River with an area of 22000km2, the length of the riverbed 323km from the Maqu River to the headwater with slope of 1.2%o. The whole source region is a Cenozoic tectonic depression situated between Buqingshan and Bar Yanhara Mountains, and can be divided into five landform units based on geomorphologic features, and show as follow from north to south: 1.Zagarishan-Buqingshan high-middle mountainous region 2.Joguzhongle Basin-Xinsuhai Lake-Gyaring Lake-Ngoring Lake-Maqu River broad-valley basin region 3.Joguzhongle Mountain-Mianshaling Ridge lower mountain-hill region 4.Kariqu River


    O. Ozcan


    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

  15. Modules for mountain shelters; Mit Arbeitspunkt auf der Almhuette

    Petzold, Katrin


    Formerly, autonomous systems installed in mountain shelters or in remote African regions had to be equipped with offgrid solar modules. This is no longer necessary. With MPPT charge control elements, low-cost standard modules can be used as well.

  16. Mountain medicin

    Bay, Bjørn; Hjuler, Kasper Fjellhaugen


    Travelling to high altitudes is an increasingly popular form of recreational holiday. Individual medical advice may be essential for certain groups of individuals such as patients with chronic disorders, pregnant women or children. This is the second part in a series of two articles on mountain...

  17. Changbai Mountains


    The Changbai Mountains are located within the boundaries of Antu County, Fusong County and Changbai County of Jilin City of Jilin Province. They cover a total area of more than 200,000 hectares and is one of the largest nature preserves in China. There are abundant species of living things, such as Dongbei Tiger, sika, sable and

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

    Ildiko VINCZE


    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.

  19. 湖泊型湿地公园色彩景观规划方法探讨--以赤山湖湿地公园为例%Study on Color Landscape Planning of Lake Wetland Park-A Case Study in the Red Mountain Lake Wetland Park

    周春予; 李明阳; 汪辉; 殳琴琴


    With the acceleration of the process of ecological civilization construction,color landscape plays an increasingly large role in people’s daily life.The function of color landscape planning in urban plan-ning,wetland planning and landscape architecture planning is increasing.In this paper,the Red Mountain Lake National Wetland Park in Jurong,Jiangsu Province was chosen as the research object and the color landscape was selected as the research starting point.The basic principles of color landscape planning were analyzed,followed by discussion of methods of color landscape planing from three spatial-temporal scales of functional subarea,touring spots and season phase change on the supporting platform of GIS in order to provide a reference for wetlands color landscape planning.%随着生态文明建设进程的加快,色彩在人们的日常生活中发挥的作用越来越大,色彩景观规划在城市规划、湿地规划、园林规划中的地位日益提高。以江苏省句容市赤山湖国家湿地公园为研究对象,选择湿地公园色彩景观作为研究的切入点,在分析湿地公园色彩景观规划基本原理基础上,在 GIS 平台支持下,从区域、景点、季相变化3个时空尺度上,探讨了湖泊型湿地公园色彩景观规划方法,以期为我国湖泊型湿地色彩景观规划提供参考。

  20. Trichloroacetic acid in the vegetation of polluted and remote areas of both hemispheres—Part II: salt lakes as novel sources of natural chlorohydrocarbons

    Weissflog, Ludwig; Elansky, Nikolai; Putz, Erich; Krueger, Gert; Lange, Christian A.; Lisitzina, Lida; Pfennigsdorff, Andrea

    One of the issues provided for by the 1993 existing substances regulation (793/93/EEC) is the assessment of the environmental risk emanating from waste materials. One such material is the highly volatile substance perchloroethene (PER; TECE). PER is produced in large quantities all over the world by the chemical industry. There are many industrial processes in which PER escapes into the environment, especially the atmosphere. It has since been proven that after entering plants via the air/leaf pathway, airborne PER can be metabolised into the phytotoxic substance trichloroacetic acid. However our own studies detected relatively high levels of TCA in environmental compartments in regions far away from industry which cannot be explained by the anthropogenic input of airborne substances into the relevant ecosystems. This indicates that natural PER emittents also exist and must be identified, in order to find out more about the global spread of PER. This paper reports on the findings of related fieldwork in the Kalmykian Steppe. This area of steppe in southern Russia spans an area extending west-to-east from the Black Sea and the Caspian Sea and north-to-south between the Greater Caucasus and Volgograd. The main aim of the experiments in the Kalmykian Steppe was to study water from lakes, rivers and springs with differing levels of salinity. The concentrations of the chlorinated hydrocarbons (VCHCs) chloroform (CHCl 3), tetrachloromethane (CCl 4), 1,1,1-trichloroethane (1,1,1-C 2H 3Cl 3), trichloroethene (TRI; C 2HCl 3), tetrachloroethene (PER; C 2Cl 4) and TCA in these waters were measured, along with the levels of cations and anions and the pH-value of the waters. The measurements indicate that in particular water from salt lakes located in semiarid/arid areas of the study region must be considered as new types of natural emittents of PER and other chlorinated hydrocarbons as well as trichloroacetic acid. Furthermore, attention is drawn to ecological impacts

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

    Teresa Korniłłowicz


    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.

  2. 户外运动基地与森林生态旅游探析--以千岛湖东山尖登山营地为例%Exploration and Analysis of Outdoor Sports Base and Forest Ecological Tourism---Take Dongshanjian Mountain Climbing Camps in Thousand-isle Lake as an Example

    陶明星; 徐高福; 彭新俊; 何俊


    户外运动基地是现代森林生态旅游的重要载体。东山尖是千岛湖环湖第一层山脊的第一高峰,具备良好的自然环境以及鲜明的文化特色。东山尖登山营地借鉴森林休闲娱乐和森林生态体验相结合的开发模式,打造以登山、滑雪、沿溪溯源和水上运动为主题的千岛湖户外运动基地,不仅丰富了千岛湖森林生态旅游的内涵,也为国有林场保护植物资源、维护森林生态以及可持续发展树立了新的标杆。%Outdoor sports base is an important carrier of modern forest eco-tourism. Dongshanjian, the highest peak in the first ridge around Thousand-isle Lake, has favorable background support, good natural environment and distinctive cultural features. Dongshanjian mountain climbing camps draws on the experience combinative development mode of forest recreation and forest ecological experience to build outdoor sports base in Thousand-isle Lake taking mountain climbing, skiing, tracing the source along the streams and wateracquatic sports as the theme, market outlook can be very promising, not only enriched the connotation of Thousand-isle Lake forest eco-tourism, also set a new benchmark for the state-owned forest farm to protect plant resources, maintaining the forest ecosystem and sustainable development.

  3. Hazards Associated with High Altitude Rain-Fed Lakes (HARL) in the Overdeepened Deglaciated Region of Hindu Kush and Himalaya

    Haritashya, U. K.; Hess, T. G.


    Mountain regions are changing rapidly as a result of climate change. It has been well established that these mountain regions are experiencing rapid glacier retreat. With accelerated retreat, glacial melt runoff can accumulate in an overdeepened glacier bed left behind by the receding glacier and can be bound by the walls of unstable frontal and lateral moraines to form a hazardous lake. However, when smaller glaciers retreat and downwaste they no longer contain enough ice to sustain the flow of water and maintain level of the lake. Furthermore, some smaller glaciers in the Hindu Kush and Himalayan region are observing extreme downwasting, which are either turning them into a rock glacier or heavily debris covered glacier leading to the reduced ice melt. Consequently, it is important to study these overdeepened beds, which are contained by the unstable mass. This is especially significant considering the great degree of complexity in the mountain weather system and recent examples of high intensity and short duration rainfall in the Hindu Kush region of Afghanistan, Karakoram region of Pakistan, and Central Himalayan region of India and Nepal. A precise understanding of mountain climate system is necessary, but so does these potentially deglaciated overdeepened beds where rain-fed lakes can form and increase systems hydrostatic pressure that can breach moraine containment and flood entire downstream region. Once lake has formed it possesses hydrological characteristics that are similar to the glacial lakes, which are known to put lives and infrastructure in danger. Therefore, in this study we evaluated overdeepened beds that are located in the complex topography and contained by abandoned or unstable lateral moraine using field and remote sensing satellite images. Our results provide degree of failure associated with these lakes based on the complex spatial and topological analysis as well as orographic distribution of the region. Such studies are not common in the

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

    Ngugi, Keziah; Ogindo, Harun; Ertsen, Maurits


    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

  5. A report from Lake Tahoe: Observation from an ideal platform for adaptive management

    Dennis D. Murphy; Patricia N. Manley


    The Lake Tahoe basin is in environmenal distress. The lake is still one of the world’s most transparent bodies of water, but its fabled clarity has declined by half since discovery of the high-mountain lake basin by explorers a century and a half ago. At that time, incredibly, objects could be observed on the lake’s bottom a hundred feet down. Two-thirds of the lake’s...

  6. Integration of Palmer Drought Severity Index and remote sensing data to simulate wetland water surface from 1910 to 2009 in Cottonwood Lake area, North Dakota

    Huang, S.; Dahal, D.; Young, Caitlin; Chander, G.; Liu, S.


    Spatiotemporal variations of wetland water in the Prairie Pothole Region are controlled by many factors; two of them are temperature and precipitation that form the basis of the Palmer Drought Severity Index (PDSI). Taking the 196km2 Cottonwood Lake area in North Dakota as our pilot study site, we integrated PDSI, Landsat images, and aerial photography records to simulate monthly water surface. First, we developed a new Wetland Water Area Index (WWAI) from PDSI to predict water surface area. Second, we developed a water allocation model to simulate the spatial distribution of water bodies at a resolution of 30m. Third, we used an additional procedure to model the small wetlands (less than 0.8ha) that could not be detected by Landsat. Our results showed that i) WWAI was highly correlated with water area with an R2 of 0.90, resulting in a simple regression prediction of monthly water area to capture the intra- and inter-annual water change from 1910 to 2009; ii) the spatial distribution of water bodies modeled from our approach agreed well with the water locations visually identified from the aerial photography records; and iii) the R2 between our modeled water bodies (including both large and small wetlands) and those from aerial photography records could be up to 0.83 with a mean average error of 0.64km2 within the study area where the modeled wetland water areas ranged from about 2 to 14km2. These results indicate that our approach holds great potential to simulate major changes in wetland water surface for ecosystem service; however, our products could capture neither the short-term water change caused by intensive rainstorm events nor the wetland change caused by human activities. ?? 2011.

  7. Estimating the volume of Alpine glacial lakes

    Cook, S. J.; Quincey, D. J.


    Supraglacial, moraine-dammed and ice-dammed lakes represent a potential glacial lake outburst flood (GLOF) threat to downstream communities in many mountain regions. This has motivated the development of empirical relationships to predict lake volume given a measurement of lake surface area obtained from satellite imagery. Such relationships are based on the notion that lake depth, area and volume scale predictably. We critically evaluate the performance of these existing empirical relationships by examining a global database of glacial lake depths, areas and volumes. Results show that lake area and depth are not always well correlated (r2 = 0.38) and that although lake volume and area are well correlated (r2 = 0.91), and indeed are auto-correlated, there are distinct outliers in the data set. These outliers represent situations where it may not be appropriate to apply existing empirical relationships to predict lake volume and include growing supraglacial lakes, glaciers that recede into basins with complex overdeepened morphologies or that have been deepened by intense erosion and lakes formed where glaciers advance across and block a main trunk valley. We use the compiled data set to develop a conceptual model of how the volumes of supraglacial ponds and lakes, moraine-dammed lakes and ice-dammed lakes should be expected to evolve with increasing area. Although a large amount of bathymetric data exist for moraine-dammed and ice-dammed lakes, we suggest that further measurements of growing supraglacial ponds and lakes are needed to better understand their development.

  8. A Remote Sensing Based Approach For Modeling and Assessing Glacier Hazards

    Huggel, C.; Kääb, A.; Salzmann, N.; Haeberli, W.; Paul, F.

    Glacier-related hazards such as ice avalanches and glacier lake outbursts can pose a significant threat to population and installations in high mountain regions. They are well documented in the Swiss Alps and the high data density is used to build up sys- tematic knowledge of glacier hazard locations and potentials. Experiences from long research activities thereby form an important basis for ongoing hazard monitoring and assessment. However, in the context of environmental changes in general, and the highly dynamic physical environment of glaciers in particular, historical experience may increasingly loose its significance with respect to impact zone of hazardous pro- cesses. On the other hand, in large and remote high mountains such as the Himalayas, exact information on location and potential of glacier hazards is often missing. There- fore, it is crucial to develop hazard monitoring and assessment concepts including area-wide applications. Remote sensing techniques offer a powerful tool to narrow current information gaps. The present contribution proposes an approach structured in (1) detection, (2) evaluation and (3) modeling of glacier hazards. Remote sensing data is used as the main input to (1). Algorithms taking advantage of multispectral, high-resolution data are applied for detecting glaciers and glacier lakes. Digital terrain modeling, and classification and fusion of panchromatic and multispectral satellite im- agery is performed in (2) to evaluate the hazard potential of possible hazard sources detected in (1). The locations found in (1) and (2) are used as input to (3). The models developed in (3) simulate the processes of lake outbursts and ice avalanches based on hydrological flow modeling and empirical values for average trajectory slopes. A probability-related function allows the model to indicate areas with lower and higher risk to be affected by catastrophic events. Application of the models for recent ice avalanches and lake outbursts show

  9. Detailed and Highly Accurate 3d Models of High Mountain Areas by the Macs-Himalaya Aerial Camera Platform

    Brauchle, J.; Hein, D.; Berger, R.


    Remote sensing in areas with extreme altitude differences is particularly challenging. In high mountain areas specifically, steep slopes result in reduced ground pixel resolution and degraded quality in the DEM. Exceptionally high brightness differences can in part no longer be imaged by the sensors. Nevertheless, detailed information about mountainous regions is highly relevant: time and again glacier lake outburst floods (GLOFs) and debris avalanches claim dozens of victims. Glaciers are sensitive to climate change and must be carefully monitored. Very detailed and accurate 3D maps provide a basic tool for the analysis of natural hazards and the monitoring of glacier surfaces in high mountain areas. There is a gap here, because the desired accuracies are often not achieved. It is for this reason that the DLR Institute of Optical Sensor Systems has developed a new aerial camera, the MACS-Himalaya. The measuring unit comprises four camera modules with an overall aperture angle of 116° perpendicular to the direction of flight. A High Dynamic Range (HDR) mode was introduced so that within a scene, bright areas such as sun-flooded snow and dark areas such as shaded stone can be imaged. In 2014, a measuring survey was performed on the Nepalese side of the Himalayas. The remote sensing system was carried by a Stemme S10 motor glider. Amongst other targets, the Seti Valley, Kali-Gandaki Valley and the Mt. Everest/Khumbu Region were imaged at heights up to 9,200 m. Products such as dense point clouds, DSMs and true orthomosaics with a ground pixel resolution of up to 15 cm were produced. Special challenges and gaps in the investigation of high mountain areas, approaches for resolution of these problems, the camera system and the state of evaluation are presented with examples.

  10. Design and improvement of the remote control self-propelled monorail transporter for mountainous orchard%自走式山地果园遥控单轨运输机的设计与改进

    李学杰; 张衍林; 张闻宇; 凌旭平


    为克服山地果园遥控单轨运输机的诸多缺陷,对原机进行优化设计。改进时取消了原机复杂的遥控装置,利用四杆-杠杆、撞块联动离合刹车机构,使运输机在轨道上能够任意自动停车和可靠制动,实现无人驾驶。用风冷汽油机替换原柴油机,增大马力、减小整机质量和外形尺寸。重新设计的防侧倒 T 形夹紧轮,可减小运输机的转弯半径,去掉原辅助轨道,降低轨道高度和安装难度,节约轨道建设成本约40%。检测试验结果表明,改进后的山地果园遥控单轨运输机可以实现爬坡角度达40°,上坡负载质量为500 kg,下坡负载质量为1000 kg,最小转弯半径小于4 m,工作可靠,运行平稳,操作简单,适合山地运输。%An improved design has been applied to the self propelled monorail transporter,which removed the complex remote control device from the original design and used simpler,more reliable and economical mechanism of the four-bar-lever linkage clutching and braking by striking so as to realize the transporter′s clutch separating and automatic,reliable braking at any point along the orbit.In this way, the unmanned driving of the vehicle can be realized.Besides,air-cooled gasoline engine has replaced the original diesel engine,which increased the horsepower and reduced the weight and overall dimensions of the machine.The design of the T grip wheel has been optimized to prevent the transporter from ske-wing.The turning radius has been reduced,the original auxiliary orbit has been removed and its altitude has been cut so that the difficulty of the installation of the orbit has been reduced and the construction costs has been lowered by 40%.The results of experiment showed that the transporter could climb up the slope of 40°with a load of 500 kg,and climb down with 1 000 kg and the minimum turning radius is less than 4 m.At the same time the monorail transporter worked reliably,ran smoothly and operated simply

  11. 75 FR 65613 - Withdrawal of Notice for Preparation of an Environmental Impact Statement for the Pine Mountain...


    ... Statement for the Pine Mountain Dam & Lake Project, AR AGENCY: Department of the Army, U.S. Army Corps of...) is withdrawing its intent to prepare an Environmental Impact Statement (EIS) for the Pine Mountain... . SUPPLEMENTARY INFORMATION: The Pine Mountain Dam project was authorized for construction by Congress in...

  12. Study on Moorburn Remote Sensing Monitoring on Poyang Lake Wetland Area and Its Influence%鄱阳湖湿地烧荒遥感监测及其影响分析

    王卷乐; 胡振鹏; 冉盈盈; 王晓龙; 张永杰


    made Poyang Lake area water body and water level of wetlands decline, even dry up. This resulted in the breeding of a large number of moss grassland in the region. Moorburn occurred frequently consequently. This is a big threat to Poyang Lake wetland nature reserve and regional ecological environment. In early 2012, the events of moorburn appeared in many places in Poyang Lake area. Facing to this urgent situation, this study, using the remote sensing quickly monitoring technology and vegetation ground investigation method, acquires the first-hand moorburn distribution area, location and vegetation growth state data. Serial knowledge are obtained based on the vegetation growth situation contrast analysis between moorburn area and non-moorburn area, and GIS buffer and overlay analysis. 1) The total patches of the moorburn region are 95 , the total area of the burned is 10278. 6196 ha, and the largest patch area is 1293 ha. Moorburn region mainly distributed in the Poyang Lake National Nature Reserve in Wucheng town, Yongxiu county, and the Nanjishan provincial wetland nature reserve in Xinjian county. 2) Moss grassland number was increased obviously in moorburn area, and its surface biomass and vegetation coverage are higher than that in non-moorburn area, but lower in the late period of growth. The vegetation height is lower in moorburn area than that in non-moorburn area in all the progress of bourgeon and growth stage. The moss grassland community species richness and biodiversity in moorburn area is lower than that in non-moorburn area obviously in the late period of growth. 3 ) GIS analysis indicates that the land cover types which were mostly influenced by the moorburn are still the dry lakebed and adjacent farmland. With the expansion of the buffer zone, the proportion of affected forests and rural settlement types increased, and more attention should be paid to this consequence. Related suggestions on wetland resources protection and moorburn management are

  13. Glacial Lake Expansion in the Central Himalayas by Landsat Images, 1990–2010

    Yong Nie; Qiao Liu; Shiyin Liu


    Glacial lake outburst flood (GLOF) is a serious hazard in high, mountainous regions. In the Himalayas, catastrophic risks of GLOFs have increased in recent years because most Himalayan glaciers have experienced remarkable downwasting under a warming climate. However, current knowledge about the distribution and recent changes in glacial lakes within the central Himalaya mountain range is still limited. Here, we conducted a systematic investigation of the glacial lakes within the entire centra...

  14. Glacial Retreat and Associated Glacial Lake Hazards in the High Tien Shan

    Smith, T. T.


    A number of studies have identified glacial retreat throughout the greater Himalayan region over the past few decades, but the Karakorum region remains an anomaly with large stagnating or advancing glaciers. The glacial behavior in the Tien Shan is still unclear, as few studies have investigated mass balances in the region. This study focuses on the highest peaks of the Tien Shan mountain range, in the region of Jengish Chokusu along the Kyrgyzstan-China-Kazakhstan border. In a first step, a 30-year time series of Landsat imagery (n=27) and ASTER imagery (n=10) was developed to track glacial growth and retreat in the region. Using a combination of spectral and topographic information, glacial outlines are automatically delineated. As several important glaciers in the study region contain medium to high levels of debris cover, our algorithm also improves upon current methods of detecting debris-covered glaciers by using topography, distance weighting methods, river networks, and additional spectral data. Linked to glacial retreat are glacial lake outburst floods (GLOFs) that have become increasingly common in High Mountain Asia over the last few decades. As glaciers retreat, their melt water is often trapped by weakly bonded moraines. These moraines have been known to fail due to overtopping caused by surge waves created by avalanches, rockslides, or glacial calving. A suite of studies throughout High Mountain Asia have used remotely-sensed data to monitor the formation and growth of glacial lakes. In a second step of the work, lake-area changes over the past 15 years were tracked monthly and seasonally using dense Landsat/ASTER coverage (n=30) with an automatic procedure based on spectral and topographic information. Previous work has identified GLOFs as a significant process for infrastructural damage in the southern Tien Shan/northern Pamir, as well as in the better studied Himalaya region. Lake identification and quantification of lake-growth rates is a valuable

  15. Rocky Mountain Spotted Fever

    ... facebook share with twitter share with linkedin Rocky Mountain Spotted Fever Rocky Mountain spotted fever is a ... New Mexico. Why Is the Study of Rocky Mountain Spotted Fever a Priority for NIAID? Tickborne diseases ...

  16. Lake Cadagno

    Tonolla, Mauro; Storelli, Nicola; Danza, Francesco


    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 cyc...

  17. [The Use of In-situ Biomonitoring to Assess the Fate and Effects of Sediment-associated Dieldrin in Lakes at the Rocky Mountain Arsenal : Drafts and Comments : 1993-1994

    US Fish and Wildlife Service, Department of the Interior — This document consists of multiple drafts of the proposal 'The Use of In-situ Biomonitoring to Assess the Fate and Effects of Sediment-associated Dieldrin in Lakes...

  18. Alpine lakes preserve mineral dust signatures: Implications for long-range mineral dust transport and Last Glacial Maximum (LGM) tornado frequency in the United States

    Bhattacharya, A.; Lora, J. M.; Pollen, A.; Vollmer, T.; Thomas, M.; Leithold, E. L.; Mitchell, J.; Tripati, A.


    The net amount of mineral dust accumulation in arid and semi-arid regions might not be entirely sourced locally or even regionally; in fact, new evidence suggests that there could be significant contributions from distal sources. The contribution from the distal sources needs to be identified, and accounted for, in order to accurately understand the meteorological and climatologic factors, both regional and global, that control mineral dust accumulation in arid and semi-arid regions. Most importantly, if identified, the two components of mineral dust accumulation- fine fraction (typically 25 microns)- could provide critical information about regional as well as global climate. There are large-scale climatological controls on the finer fraction of mineral dust, while the coarser fraction is related to intense invents (i.e., the occurrence of cyclones). However, studies attempting to separate these two size fractions in terrestrial archives have been limited. Here we separate the two size fractions using grain size analysis, and use trace element analysis in each size fraction to identify contributing source regions. We apply this technique to well-dated cores collected from three lakes that are distributed across the western, southwestern and Great Plains in the United States: Pear Lake in the Sierra Nevada Mountains (CA), Senator Beck Lake in the San Juan Mountains (CO), and North Lake (WY). These lakes are uniquely situated to monitor dust fluxes; previous studies have demonstrated that sedimentation in these lakes are dominated by mineral dust accumulation; there is also evidence of remotely and locally sourced dust in these lakes, and of textural differences between the two types of dust fractions. We compare our results with previously published data on dust from loess deposits in the United States, and isotopic modeling (LMDZ). We find evidence that the finer-grain size fraction in alpine lake cores could be of remote origin; work is underway to quantify this


    Petre GÂŞTESCU


    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.

  20. Remote Research

    Tulathimutte, Tony


    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.

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

    Neal Michelutti


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

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


    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

  3. Remote Sensing

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


    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.

  4. Lake Titicaca - Physics of an Inherited Hydropower Macroproject Proposal

    Cathcart, R


    Shared almost evenly by Peru and Bolivia, Lake Titicaca is situated on an Altiplano endorheic region of the northern Andes Mountains. Rio Desaguadero is the lake only outlet. From 1908, several macro-engineers speculated on the creation of a second, completely artificial, outlet for Lake Titicaca freshwater. Here we reconsider several 20th Century macroproject proposals, with the goal of examining and enhancing this technically interesting South American 21st Century Macro-engineering inheritance.

  5. A simple method to estimate fractal dimension of mountain surfaces

    Kolwankar, Kiran M


    Fractal surfaces are ubiquitous in nature as well as in the sciences. The examples range from the cloud boundaries to the corroded surfaces. Fractal dimension gives a measure of the irregularity in the object under study. We present a simple method to estimate the fractal dimension of mountain surface. We propose to use easily available satellite images of lakes for this purpose. The fractal dimension of the boundary of a lake, which can be extracted using image analysis softwares, can be determined easily which gives the estimate of the fractal dimension of the mountain surface and hence a quantitative characterization of the irregularity of the topography of the mountain surface. This value will be useful in validating models of mountain formation

  6. The potential effects of Rocky Mountain Arsenal cleanup and Denver metropolitan transportation development on bald eagles

    US Fish and Wildlife Service, Department of the Interior — The U.S. Army's Rocky Mountain Arsenal and Colorado's Barr Lake State Park provide habitats which support wintering and nesting bald eagles near metropolitan Denver,...

  7. Mapping hazards from glacier lake outburst floods based on modelling of process cascades at Lake 513, Carhuaz, Peru

    Schneider, Demian; Huggel, Christian; Cochachin, Alejo; Guillén, Sebastiàn; García, Javier


    Recent warming has had enormous impacts on glaciers and high-mountain environments. Hazards have changed or new ones have emerged, including those from glacier lakes that form as glaciers retreat. The Andes of Peru have repeatedly been severely impacted by glacier lake outburst floods in the past. An important recent event occurred in the Cordillera Blanca in 2010 when an ice avalanche impacted a glacier lake and triggered an outburst flood that affected the downstream communities and city of...

  8. Mapping hazards from glacier lake outburst floods based on modelling of process cascades at Lake 513, Carhuaz, Peru

    Schneider, D; C. Huggel; Cochachin, A.; Guillén, S.; García, J.


    Recent warming has had enormous impacts on glaciers and high-mountain environments. Hazards have changed or new ones have emerged, including those from glacier lakes that form as glaciers retreat. The Andes of Peru have repeatedly been severely impacted by glacier lake outburst floods in the past. An important recent event occurred in the Cordillera Blanca in 2010 when an ice avalanche impacted a glacier lake and triggered an outburst flood that affected the downstream commu...

  9. Microbial community structure in moraine lakes and glacial meltwaters, Mount Everest.

    Liu, Yongqin; Yao, Tandong; Jiao, Nianzhi; Kang, Shichang; Zeng, Yonghui; Huang, Sijun


    The bacterial diversity and abundance in two moraine lakes and two glacial meltwaters (5140, 5152, 5800 and 6350 m above sea level, respectively) in the remote Mount Everest region were examined through 16S rRNA gene clone library and flow cytometry approaches. In total, 247 clones were screened by RFLP and 60 16S rRNA gene sequences were obtained, belonging to the following groups: Proteobacteria (8% alpha subdivision, 21% beta subdivision, and 1% gamma subdivision), Cytophaga-Flavobacteria-Bacteroides (CFB) (54%), Actinobacteria (4%), Planctomycetes (2%), Verrucomicrobia (2%), Fibrobacteres (1%) and Eukaryotic chroloplast (3%), respectively. The high dominance of CFB distinguished the Mount Everest waters from other mountain lakes. The highest bacterial abundance and diversity occurred in the open moraine lake at 5152 m, and the lowest in the glacial meltwater at 6350 m. Low temperature at high altitude is considered to be critical for component dominancy. At the same altitude, nutrient availability plays a role in regulating population structure. Our results also show that the bacteria in Mount Everest may be derived from different sources.

  10. A View from the Mountain Top: The Purple Mountain Observatory Library, China

    Zhang, Jian


    This paper discusses the author's experience directing the Purple Mountain Observatory Library, Chinese Academy of Sciences (CAS) in Nanjing, China. Routine collection development, management and preservation issues are described, and the unique challenges and opportunities involved in operating a remote observatory library are highlighted.

  11. 巢湖水体漫衰减系数空间差异及其遥感反演%Spatial variability and diffuse attenuation coefficient of remote sensing inversion in Lake Chaohu

    金鑫; 朱利; 吴传庆; 李云梅; 王桥; 刘忠华; 王彦飞; 尹斌; 张红; 徐袆凡; 徐昕


    根据2009年6月巢湖32个样点的实测数据,分析巢湖水体漫衰减系数光谱特征、主导因子、空间分布规律以及400-700nm各波段Kd与Kd(490)之间的关系,并在此基础上,建立了Kd的遥感反演模型.结果表明:巢湖水体Kd具有一致的光谱特征,400-600nm之间Kd随波长的增加呈指数衰减趋势,在600-700nm之间的变化较小,部分点位在波长675nm附近出现峰值,700-900nm之间Kd呈现出类似于纯水的吸收光谱特征;巢湖中无机颗粒物是水体漫衰减的主导因子,有机悬浮物影响次之,CDOM的影响最小;巢湖东半湖区Kd(490)普遍高于西半湖区,巢湖中部Kd(490)等值线分布较密集,湖区其他部分则相对稀疏;利用591、702、842nm处的遥感反射率进行多元线性回归反演得到的Kd(490)与实测Kd(490)之阳J的平均相对误差为7.85%;同时,400-550nm波段范围内,可以利用线性关系和Kd(490)对Kd(λ,λ≠490nm)进行参数化表示,在550-700nm波段范围则可采用常数与Kd(490)的乘积来表示Kd(λ,λ≠490nm).通过遥感反射率反演Kd(490),进而推算Kd(λ),其结果与实测Kd之间的平均相对误差为6.14%.%According to the in situ measured data on 32 sampling sites in Lake Chaohu in June 2009, the spectral characteristics of diffuse attenuation coefficient (Kd ), dominant factors, spatial distribution, as well as the relationship between Kd and Ka (490) in 400-700nm bands were analyzed.On the basis of these analysis, remote sensing inversion model was developed to calculate Kd (490).The results indicate that Kd presented the consistent spectral characteristics.The Kd in 400 -600nm showed a exponential decay trend, but Ka from 600nm to 700nm didn't correlate with wavelength.Due to the higher concentration of phytoplankton in some locations, peak values of Kd appeared at 675nm; but Ka showed a feature that was similar to that of pure water in 700 -900nm.The dominant factor of diffuse attenuation coefficient was

  12. Application of Remote Sensing for Surveillance of Snail Habitats in Poyang Lake, China%遥感用于鄱阳湖区钉螺孳生地的监测

    伍卫平; 陈红根; Peng Gong; 冯正; George Davis; 刘红云; Edmund Seto; 吕尚标; 张晶; 华政辉; 郭家钢; 林丹丹


    目的结合遥感技术和地面生态学调查数据区分钉螺孳生地并监测其变化.方法从鄱阳湖共选择100个调查点,75个为从鄱阳湖574块草洲中随机抽取.根据历史调查(1982~1984),其中50个有螺,25个无螺,另25个为非钉螺孳生地调查点.将每个调查点(面积10 000 m2)分成100格,从中随机抽取20格,在每格的中央置钉螺调查框(4 m2),收集框内所有钉螺.收集与地面调查同期的TM卫片.采用非监督分类法对卫片进行分类并结合地面调查结果区分钉螺孳生地.结果分类的敏感性和特异性分别为90.0%~95.6%和61.1%~68.6%.1 999~2000年,鄱阳湖区估算的钉螺孳生地面积变幅为623.4~762.8 km2.结论钉螺孳生地与植被覆盖的区域有关,卫片分类能用于区分钉螺孳生地确定其范围并监测其随关键因素的波动而造成的变化.%Objective To identify snail habitats and monitor the changes by combining remote sensing technique with the ground-based ecological data. Methods Of 100 survey sites selected throughout Poyang Lake, 75 were randomly identified from 574 land mass units: 50 were from snail habitats and 25 were from non-snail habitats based on a historicalsurvey (1982-1984); 25 sites with habitats that did not have snails were also selected. Each site, covering 10 000 m2 , wasdivided into a grid of 100 cells from which 20 cells were randomly selected. Snails, when present, were collected from a 4m2 frame placed in the center of the selected cell. Satellite Landsat TM images were obtained for the same period as the ground survey data collected. Unsupervised classification was used to classify the images. Identified land-cover types were correlated with snail habitat. Results The sensitivity and specificity of classified snail habitat were 90. 0%-95.6%and 61.1% -68.6%, respectively. Based on the classification, estimated snail habitat areas in Poyang Lake increased from 623.4 km2 in 1999 to 762.8 km2 in 2000. Conclusion

  13. Glacial lake outburst floods from Kyagar Glacier, Karakoram, P. R. China

    Haemmig, Christoph; Huss, Matthias; Keusen, Hansrudolf; Hess, Josef; Wegmüller, Urs; Ao, Zhigang; Kulubayi, Wubuli


    Kyagar Glacier is located in the Karakoram Mountains in the southwest of Xinjiang Uygur Autonomous Region, P.R. China. The glacier tongue entirely blocks the riverbed of the upper Shaksgam Valley and impounds a glacial lake at 4750 m a.s.l., which was the source of several violent and disastrous Glacial Lake Outburst Floods (GLOF) over the past decades. The spontaneous floods are a threat to over 1 mio. inhabitants in the floodplains of the Yarkant River. A GLOF early warning system, combining satellite remote sensing and two terrestrial observation and warning stations at Kyagar Lake and 200 km downstream, was implemented in 2011 and 2012. The stations provide daily images based on automatic cameras, water level measurements, and are equipped with weather sensors to monitor local climate. We discuss the GLOF early warning system and present first measurement series of melt-water runoff and meteorological conditions from one of the remotest regions of the Karakoram mountains. The ongoing project also elaborates scenario-based forecasts of future glacier lake developments, considering the ice-flow dynamics of Kyagar Glacier as well as surface mass-balance response to climate change. Comparison of two high-resolution Digital Elevation Models (DEMs) for the ice dam show surface lowering rates of more than 4 m a-1 between 2002 and 2011 leading to a significant reduction in lake volume and hence, a decreasing GLOF hazard potential. Glacier melt modelling using climate scenarios indicates a rapid retreat of the glacier tongue over the next decades. However, two DEMs covering the entire glacier for 2000-2008 show small elevation changes in the accumulation area and even a slight mass gain in the central part. This is supported by the observation of a moderate ice-flow speed-up in this region. This pattern is typical for surge-type glaciers and is consistent with the numerous documented glacier surges in the Karakoram. Furthermore, the displacement rate of the glacier

  14. Acidification in the mountains ?; Foersurning i fjaellen

    Degerman, E. [National Board of Fisheries, Drottningholm (Sweden). Inst. of Freshwater Research; Engblom, E.; Lingdell, P.E. [Limnodata AB, Skinnskatteberg (Sweden); Melin, E.; Olofsson, E. [Haerjedalens Kommun, Sveg (Sweden)


    The present paper is a literature review dealing with the extent of acidification in the Swedish mountain range. The first effects of acidification were noted in the beginning of the 1960`s in the Fulufjaell area in the southernmost part of the mountain range. Since then many studies have been published indicating that the extent of acidification and the negative effects of biota were widespread. However, many scientists have claimed that there is no acidification in the area and that acid surges following snow melt have always been a problem to the fauna due to natural dilution of the water. This is contradicted by this paper. Acidification in this area is caused by anthropogenic emissions of acidifying substances. It is shown that the mountain area has a higher load of airborne pollutants than the surrounding lowland. Lakes are not as badly affected as streams, but an overall loss of alkalinity is found in the entire mountain range and several small ephemeral lakes in the southern part of the range have lost alkalinity completely. There are indications that acidification also affects lichens (Cladonia spp.) negatively, and it is suspected that the abundance of epilithic green algae has increased in streams. Relatively few objects have been limed so far. Re colonization of benthos, fish and birds has been noted after liming. It is recommended that the liming programme is extended. The ultimate goal should be to achieve a pH above 5 in snow to avoid harmful effects to the most sensitive water bodies. 307 refs

  15. Toward mountains without permanent snow and ice

    Huss, M.; Bookhagen, B.; Huggel, C.; Jacobsen, D.; Bradley, R. S.; Clague, J. J.; Vuille, M.; Buytaert, W.; Cayan, D. R.; Greenwood, G.; Mark, B. G.; Milner, A. M.; Weingartner, R.; Winder, M.


    The cryosphere in mountain regions is rapidly declining, a trend that is expected to accelerate over the next several decades due to anthropogenic climate change. A cascade of effects will result, extending from mountains to lowlands with associated impacts on human livelihood, economy, and ecosystems. With rising air temperatures and increased radiative forcing, glaciers will become smaller and, in some cases, disappear, the area of frozen ground will diminish, the ratio of snow to rainfall will decrease, and the timing and magnitude of both maximum and minimum streamflow will change. These changes will affect erosion rates, sediment, and nutrient flux, and the biogeochemistry of rivers and proglacial lakes, all of which influence water quality, aquatic habitat, and biotic communities. Changes in the length of the growing season will allow low-elevation plants and animals to expand their ranges upward. Slope failures due to thawing alpine permafrost, and outburst floods from glacier- and moraine-dammed lakes will threaten downstream populations. Societies even well beyond the mountains depend on meltwater from glaciers and snow for drinking water supplies, irrigation, mining, hydropower, agriculture, and recreation. Here, we review and, where possible, quantify the impacts of anticipated climate change on the alpine cryosphere, hydrosphere, and biosphere, and consider the implications for adaptation to a future of mountains without permanent snow and ice.

  16. Regulatory factors in crustacean zooplankton assemblages in mountain lakes of northern Chilean Patagonia (38-41°S: a comparison with Bulgarian counterparts (42°N Factores reguladores en ensambles de crustáceos zooplanctónicos en lagos de montaña del norte de la Patagonia chilena (38-41°S: una comparación con sus contrapartes de Bulgaria (42°N

    Patricio De los Ríos-Escalante


    Full Text Available Chilean Patagonia has protected mountainous areas with evergreen native forests; in which the lakes and rivers, of volcanic or glacial origin, are oligotrophic. In Bulgaria, there are mountainous zones with native forests and associated lakes of volcanic origin. The aim of the present study is to carry out a preliminary comparison of zooplanktonic crustaceans in lake ecosystems associated with native forests of Chilean Patagonia and of Bulgarian mountains. The study revealed that the lakes studied in Chilean Patagonia are associated mainly with Nothofagus forests; they are oligotrophic, with a low number of zooplanktonic crustacean species. Similar results were observed for Bulgarian mountain lakes associated with Fagus forests. A null model analysis of species co-occurrence was applied to the two groups of lakes, and the result revealed the absence of regulatory factors in species associations. These studies agree with similar descriptions of lakes in Andean Patagonia and New Zealand. They highlight the important role of native Nothofagus forests in Argentina and Chile, and of Fagus forests with associated soil properties in Bulgaria, in the oligotrophy of the lakes studied.La Patagonia de Chile tiene una serie de áreas protegidas con bosques nativos perennes asociados a lagos y ríos oligotróficos y de origen glacial. Por otro lado en Bulgaria hay una serie de zonas montañosas con lagos asociados de origen volcánico o glacial. El objetivo del presente trabajo es realizar una primera descripción de especies de crustáceos zooplanctónicos en ecosistemas lacustres asociados a bosques nativos en la Patagonia de Chile y en las montañas de Bulgaria. Los estudios indican que los lagos de la Patagonia de Chile están asociados principalmente con bosques de Nothofagus, mientras que similares resultados fueron observados en lagos de Bulgaria con bosques de Fagus. La regresión lineal entre concentración de clorofila y número de especies para

  17. Contaminant Monitoring Strategy for Henrys Lake, Idaho

    John S. Irving; R. P. Breckenridge


    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

  18. 76 FR 29264 - Minor Boundary Revision at Rocky Mountain National Park


    ... National Park Service Minor Boundary Revision at Rocky Mountain National Park AGENCY: National Park Service....S.C. 4601-9(c)(1), the boundary of Rocky Mountain National Park is modified to include an additional... National Park and northeast of Grand Lake. The boundary revision is depicted on Map No. 121/105,475...

  19. Afghanistan - Debris Covered Glaciers, Supraglacial Lakes, and the Potential for Catastrophic Flooding (Jökulhlaups)

    Molnia, B. F.


    Included in the U.S. Geological Survey’s investigation of glaciers and the water resources of Afghanistan is a component focused on determining the potential for catastrophic flooding (jökulhlaups). In glacier environments, jökulhlaups are usually caused by: (1) drainage of ice-dammed lakes; (2) drainage of ice-marginal lakes (typically moraine-dammed lakes); (3) release of water stored subglacially, englacially, or supraglacially, sometimes through surge-related processes; or (4) through melting of glaciers located around the summit craters of erupting volcanoes. All but the last potential cause may lead to significant flooding from Himalayan Mountain glaciers. The primary data sets being investigated are: (1) VNIR (visible and near-infrared) digital images collected between 2001 and 2006 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on the Terra spacecraft; (2) Landsat 7 Thematic Mapper (ETM+) multispectral data collected between 1998 and 2004; and (3) Google Earth space photography subscenes imaged between 2006 and 2008. GIS analysis, an automated supervised classification, a manual visual image analysis, and a remote sensing assessment were performed on these data to determine the number, location, size, area, aspect, distribution of ice-surface and ice-marginal lakes, and many other parameters of about 1,000 glaciers in Afghanistan’s Wakhan Pamir. There, all of the glaciers analyzed are thinning and/or retreating. In this type of environment, it is not unusual for a significant amount of the meltwater thus produced to be temporarily stored within the glacier system. Many Wakhan Pamir valley glaciers are debris covered. Often significant parts of the ablation zone surface of these glaciers host supraglacial lakes. Typically, these supraglacial lakes develop on stagnant or slowly moving ice through thermokarst processes. Many of these valley glaciers are also characterized by the presence of empty thermokarst pits

  20. Geography of Alaska Lake Districts: Identification, Description, and Analysis of Lake-Rich Regions of a Diverse and Dynamic State

    Arp, Christopher D.; Jones, Benjamin M.


    Lakes are abundant landforms and important ecosystems in Alaska, but are unevenly distributed on the landscape with expansive lake-poor regions and several lake-rich regions. Such lake-rich areas are termed lake districts and have landscape characteristics that can be considered distinctive in similar respects to mountain ranges. In this report, we explore the nature of lake-rich areas by quantitatively identifying Alaska's lake districts, describing and comparing their physical characteristics, and analyzing how Alaska lake districts are naturally organized and correspond to climatic and geophysical characteristics, as well as studied and managed by people. We use a digital dataset (National Hydrography Dataset) of lakes greater than 1 hectare, which includes 409,040 individual lakes and represents 3.3 percent of the land-surface area of Alaska. The selection criteria we used to identify lake districts were (1) a lake area (termed limnetic ratio, in percent) greater than the mean for the State, and (2) a lake density (number of lakes per unit area) greater than the mean for the State using a pixel size scaled to the area of interest and number of lakes in the census. Pixels meeting these criteria were grouped and delineated and all groups greater than 1,000 square kilometers were identified as Alaska's lake districts. These lake districts were described according to lake size-frequency metrics, elevation distributions, geology, climate, and ecoregions to better understand their similarities and differences. We also looked at where lake research and relevant ecological monitoring has occurred in Alaska relative to lake districts and how lake district lands and waters are currently managed. We identified and delineated 20 lake districts in Alaska representing 16 percent of the State, but including 65 percent of lakes and 75 percent of lake area. The largest lake districts identified are the Yukon-Kuskokwim Delta, Arctic Coastal Plain, and Iliamna lake districts with

  1. EAARL Coastal Topography--North Shore, Lake Pontchartrain, Louisiana, 2010

    U.S. Geological Survey, Department of the Interior — A digital elevation model (DEM) of a portion of the north shore of Lake Pontchartrain, Louisiana, was produced from remotely sensed, geographically referenced...

  2. EAARL Coastal Topography--North Shore, Lake Pontchartrain, Louisiana, 2010

    U.S. Geological Survey, Department of the Interior — A digital elevation model (DEM) of a portion of the north shore of Lake Pontchartrain, Louisiana, was produced from remotely sensed, geographically referenced...

  3. Remote Sensing.

    Williams, Richard S., Jr.; Southworth, C. Scott


    The Landsat Program became the major event of 1982 in geological remote sensing with the successful launch of Landsat 4. Other 1982 remote sensing accomplishments, research, publications, (including a set of Landsat worldwide reference system index maps), and conferences are highlighted. (JN)

  4. Remote medicine



    The international oil industry, catalyzed by a surge in exploration and production projects in remote regions, is giving health care for its travelers and expatriates a high priority. L.R. Aalund, the Journal`s Managing Editor--Technology, reports on why and how this is happening now. He covers this in articles on: health care in Russia, air ambulance evacuations, and the deployment of remote paramedics. Aalund gathered the information during trips to Finland and Russia and interviews with oil industry personnel, physicians, and other medical professionals in North America, Europe, and Siberia. Titles of the four topics presented in this special section on remote medicine are as follows: Oil companies focus on emergency care for expats in Russia; Air ambulance plan can be critical; Remote paramedics have high level of training; and Other facets of remote medicine.

  5. Limnological Assessment of West Point Lake, Georgia


    1977). "A trophic state index for lakes," Limnology and Oceanography 22(2), 361-369. Cherry, R. N., Lium, B. W., Shoaf, W. T., Stainer , J. K., and...34 Journal of Freshwater Ecology 3, 175-179. Hakanson, L. and Jansson, M. (1983). Principles of Lake Sedimentology Springer-Verlag, New York. Johnson , R. W...48 International Geoscience-Remote Sensing Symposium. University of Maryland, College Park, MD, 289-292. Kennedy, R. H., Johnson , K, and Long, K. (1993

  6. 喜马拉雅山地区冰川湖溃决灾害隐患遥感调查及影响因素分析%Remote sensing investigation and influence factor analysis of glacier lake outburst potential in the Himalayas

    刘春玲; 童立强; 祁生文; 张世殊; 郑博文


    喜马拉雅山地区的冰川湖(简称“冰湖”)受形成条件和自然环境的影响,往往会发生溃决,造成洪水和泥石流灾害,严重威胁人类生产和生活、生存与发展,成为该地区一重大地质灾害隐患。采用QuickBird和ETM等卫星遥感数据,结合野外考察,研究喜马拉雅山地区冰湖溃决灾害隐患后认为:①喜马拉雅山地区的冰湖在区域分布上具有由东南向西北逐步递减的趋势,冰湖分布最多的是山南、日喀则、林芝和阿里地区,分布密度最大的是山南地区的洛扎一带;②喜马拉雅山地区存在19个溃决灾害隐患的冰湖,均为冰川终碛湖,其中13个湖存在重大溃决灾害隐患,6个存在较大溃决灾害隐患;③引起冰川终碛湖溃决的激发因素较多,其中冰湖周围的冰崩、雪崩、基岩崩塌和滑坡入湖涌浪溃坝是最重要的原因。研究结果对西藏地区冰湖溃决灾害的预警与防治具有重要意义。%Under the impact of formation conditions and natural environment , moraine -dammed lake outbursts take place frequently and then give rise to floods and mudslides , which menaces people's production , life, survival and development and becomes one of the great geohazard hidden dangers in the Himalayas .Using QuickBird and ETM data of remote sensing satellite and combining the investigations in field work , the authors studied the glacier lake outburst potential .The research results show that the areal distribution of glacier lakes presents a trend of decrease gradually from SE to NW in the Himalayas .Most of the glacier lakes are distributed in Shannan , Shigatse , Nyingchi and Ngari .The region of maximal distribution density is Lho -brag area of Shannan .It can be found that there are nineteen glacier lakes , all of which are moraine -dammed lakes that have outburst hazard potential . Among the nineteen glacier lakes , there are 13 glacier lakes having great


    郭家钢; 陈红根; 林丹丹; 胡广汉; 吴晓华; 李东; 刘红云; 郑江; 陈名刚


    Objective To identify Onocmelania snail habitats and areas with high transmission potential by using Geographic Information System (GIS) and Remote Sensing (RS). Methods Marshland areas near high endemic villages of schistosomiasis in the Poyang Lake region were selected. Corresponding map was digitized and (Landsat 5 TM) the image was corrected according to the digital map. The image where water and land shifted during floody and dry seasons was extracted and classified by unsupervised method. The image in dry seasons was calculated by both Normalized Difference Vegetation Index (NDVI) and Tasseled Cap model. Traditional snail survey was done at the same areas and recorded the geographic position by Geographic Position System (GPS). Some cultured lands inside the embankment and water pound in marshland areas were selected as control group. Results The image of pilot areas was classified into 10 classes. The value of image after classification was extracted according to snail habitat spots as well as cultured land and water spots. The result shows snails spots distributed in class 6,7 and 8. Farther analysis of both NDVI and Tasseled Cap model shows that the snail habitats were mainly distributed in the NDVI value of more than 115, and in Tasseled Cap wetness value between -10 to 3, while the most cultured lands, inside the embankment and water pound in marshland distributed out of these values. Conclusion The marshland shifting water to land and with healthy vegetation is correlated to snail habitats in the Poyang Lake. TM data analysis shows 94.93% correction with three steps to identify the snail habitats: first step, to highlight the class 6, 7 and 8 by unsupervised classification to define the snail habitat environment; second step, to extract the value by NDVI model, where NDVI value is more than 110 so as to define a healthy vegetation as snail suspicious habitat, and third step, to use Tasseled Cap wetness model to define the areas which value is between

  8. Major Elements in Lake Muhazi, Rwanda, East Africa

    Jean de la Paix MUPENZI; GE Jiwen; Gabriel HABIYAREMYE


    The aim of this study undertaken at Lake Muhazi in Rwanda was to determine and analyze the major elements present in water. The presence of many major elements (Al, As, Ba, C, Ca, Cu,Fe, H+, K, Mg, Mn, N, P, S, Si, and Zn) was determined by spectroscopic technique. The concentrations of the elements were measured in water samples taken from three different locations of the lake from May to August 2008. The lake is polluted by water flow from mountain sides surrounding the lake. Other causes of pollution could be the use of agrocbemicals in the sugar land, which surrounds the lake, and human activities near the lake. Finally, we proposed the strategies that can be applied in order to ensure good conservation of the environment and to prevent augmentation of heavy materials into the lake.

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

    Jansky, Bohumir; Yerokhin, Sergey; Sobr, Miroslav; Engel, Zbynek; Cerny, Michal; Falatkova, Kristyna; Kocum, Jan; Benes, Vojtech


    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.