Remote High Altitude Research Articles

A rare case of impacted mandibular distomolar: Identification and management at a remote high altitude location

Planning the surgical extraction of an impacted supernumerary tooth poses a very peculiar problem for a dental professional. The management of this unique clinical situation is quite challenging and requires meticulous preparation, especially in a remote high altitude regions. Supernumerary teeth are those which are present in excess of the normal permanent or deciduous dentition in the oral cavity. A distomolar, also commonly known as the fourth molar, is a supernumerary tooth located distal to the third molars. The occurrence of supernumerary teeth is much more frequently observed in the maxillary arch as compared to the mandible. While the distomolar is quite infrequently observed, its occurrence in the mandible is even rarer. In this article, we present an overview of distomolars along with a case report on the management of a symptomatic mandibular distomolar at a remote setup in Tangtse region of the Union Territory of Ladakh.

Calibration and assessment of electrochemical low-cost sensors in remote alpine harsh environments

Abstract. This work presents results from an original open-source low-cost sensor (LCS) system developed to measure tropospheric O3 in a remote high altitude alpine site. Our study was conducted at the Col Margherita Observatory (2543 m above sea level), in the Italian Eastern Alps. The sensor system mounts three commercial low-cost O3/NO2 sensors that have been calibrated before field deployment against a laboratory standard (Thermo Scientific; 49i-PS), calibrated against the standard reference photometer no. 15 calibration scale of the World Meteorological Organization (WMO). Intra- and intercomparison between the sensors and a reference instrument (Thermo Scientific; 49c) have been conducted for 7 months from May to December 2018. The sensors required an individual calibration, both in laboratory and in the field. The sensor's dependence on the environmental meteorological variables has been considered and discussed. We showed that it is possible to reduce the bias of one LCS by using the average coefficient values of another LCS working in tandem, suggesting a way forward for the development of remote field calibration techniques. We showed that it is possible reconstruct the environmental ozone concentration during the loss of reference instrument data in situations caused by power outages. The evaluation of the analytical performances of this sensing system provides a limit of detection (LOD) <5 ppb (parts per billion), limit of quantification (LOQ) <17 ppb, linear dynamic range (LDR) up to 250 ppb, intra-Pearson correlation coefficient (PCC) up to 0.96, inter-PCC >0.8, bias >3.5 ppb and ±8.5 at 95 % confidence. This first implementation of a LCS system in an alpine remote location demonstrated how to obtain valuable data from a low-cost instrument in a remote environment, opening new perspectives for the adoption of low-cost sensor networks in atmospheric sciences.

Aerosol Optical Properties over Gurushikhar, Mt. Abu: A High Altitude Mountain Site in India

Continuous and simultaneous measurements of aerosol optical properties (the scattering and absorption coefficients) were conducted, for the first time, at a mountain site, Gurushikhar, Mt. Abu, in the Aravalli Range in western India from January 2015 to December 2016. The aerosol scattering and absorption coefficients were higher in the afternoon than during the forenoon and night because of atmospheric boundary layer dynamics that, when accompanied by strong thermal convection, promote an upward movement of pollutants to the observational site from the surrounding foothills. The aerosol scattering and absorption coefficients exhibited a strong seasonal variability. The average scattering coefficients during the winter, premonsoon, monsoon and postmonsoon seasons were 78.5 ± 22.9, 61.8 ± 12.2, 49.9 ± 25.1 and 121.8 ± 47.4 Mm–1, respectively, and the corresponding absorption coefficients were 14.9 ± 3.1, 9.1 ± 2.9, 5.1 ± 3.2 and 20.2 ± 10.2 Mm–1. The single scattering albedo also exhibited a significant seasonal variation, with the maximum occurring during the monsoon season (0.91) and the minimum during winter (0.83). The mean annual I²sca, I²abs and SSA at 550 nm were 74 ± 34 Mm–1, 12 ± 7 Mm–1 and 0.87 ± 0.04. These results indicate that Gurushikhar, a remote high altitude site, is influenced by local and long-range transported aerosols through convection and advection processes. However, the aerosol properties at this pristine location are governed by transported emissions rather than local anthropogenic sources and also display low inter-annual variability. Thus, Gurushikhar can be considered a background site for the nearby source regions in western India.

High altitude with monotonous environment has significant impact on mood and cognitive performance of acclimatized lowlanders: Possible role of altered serum BDNF and plasma homocysteine level

BackgroundMonotony resulting due to the wilderness, sparse population and isolation from society could adversely affect human physiology and cause mood alterations. Thus, observations need to be conducted in order to elucidate the possible role of circulating biomarkers in inducing altered mood and cognitive performance following prolonged exposure to high altitude (HA) with persistent monotonous environment. ObjectiveThe present study aimed towards investigating the impact of monotonous environment in remote HA on mood and cognitive performance of human volunteers and its correlation with serum brain derived neurotrophic factor (BDNF) and plasma homocysteine level. MethodsThe present study was conducted on male lowlander participants who had normal social life prior to induction in HA environment. Baseline data was acquired at altitude ≤240 m mean sea level (MSL). Thereafter, the participants were inducted to an altitude of 4500–4800 m MSL. After acclimatization to HA, the participants were assigned as acclimatized low landers (ALL). Longitudinal follow up was conducted after 8 months of high altitude induction on acclimatized low landers (8ALL). Further, to study the effect of monotony, the participants were randomly assigned into different group sizes during their further stay of 4 months in HA viz. ≤5 (12ALL ≤ 5) and ≥10 (12ALL ≥ 10). Mood and cognitive performance of the participants were assessed by standard self-administered questionnaires. Serum BDNF and plasma homocysteine were estimated and their correlation with mood and cognition were determined. ResultsThe findings showed significantly low serum BDNF in 12ALL ≤ 5 group when compared to baseline, 8ALL and 12AL ≥ 10 groups. Alleviated serum BDNF was associated with increased prevalence of mood alterations in HA with persistent monotonous environment. Participants of 12ALL ≥ 10 group showed significantly higher cognitive performance as compared to 12ALL ≤ 5 group which was associated with reduced plasma homocysteine level. LimitationsTotal registered volunteers during baseline study were not available during the entire period of this study. The second limitation was exclusion of participants with medical history of severe head injuries, chronic diseases in family and extreme baseline serum profile. Third limitation of the study was to exclude the participants detected with MCI after 8 months of HA induction for negating the role of hypobaric hypoxia on mood and cognition. ConclusionThe study advocated that ALLs of 12ALL ≤ 5 group have increased prevalence of depressive trait and cognitive impairment which was correlated with reduced serum BDNF and augmented plasma homocysteine level as compared to participants of 12ALL ≥ 10 group having better social interaction with improved cognition and mood. The basic findings of the present study revealed that prolonged HA stay after physiological acclimatization should be regulated by proper social interaction involving normal group size to avoid detrimental effect of monotony and its significant impact on circulatory biomarkers.

Inversion Approach to Validate Mercury Emissions Based on Background Air Monitoring at the High Altitude Research Station Jungfraujoch (3580 m).

The reduction of emissions of mercury is a declared aim of the Minamata Convention, a UN treaty designed to protect human health and the environment from adverse effects of mercury. To assess the effectiveness of the convention in the future, better constraints about the current mercury emissions is a premise. In our study, we applied a top-down approach to quantify mercury emissions on the basis of atmospheric mercury measurements conducted at the remote high altitude monitoring station Jungfraujoch, Switzerland. We established the source-receptor relationships and by the means of atmospheric inversion we were able to quantify spatially resolved European emissions of 89 ± 14 t/a for elemental mercury. Our European emission estimate is 17% higher than the bottom-up emission inventory, which is within stated uncertainties. However, some regions with unexpectedly high emissions were identified. Stationary combustion, in particular in coal-fired power plants, is found to be the main responsible sector for increased emission estimates. Our top-down approach, based on measurements, provides an independent constraint on mercury emissions, helps to improve and refine reported emission inventories, and can serve for continued assessment of future changes in emissions independent from bottom-up inventories.

Mercury and Selected Trace Elements from a Remote (Gosainkunda) and an Urban (Phewa) Lake Waters of Nepal

Two lakes, one from the remote high altitude on the southern slope of the Himalaya (Lake Gosainkunda) and another from the urban mid-hill area (Lake Phewa) were studied for evaluating anthropogenic inputs of the pollutants, particularly mercury (Hg) and other trace elements (TEs) (such as Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb). A total of 77 water samples, 24 from Lake Gosainkunda and 53 from Lake Phewa were collected from different depth profiles during October/November 2010. Concentrations of Hg were significantly higher in Lake Gosainkunda compared to Lake Phewa probably due to long-range transport of Hg and its deposition on high altitudes of the Himalayas, in addition to the probable natural geological sources. Some of the TEs (such as Al, V, Cr, Mn, Fe, and Co) show crustal origin in Lake Gosainkunda, whereas others such as Ni, Cu, Zn, Cd, and Pb indicate possible anthropogenic origin (enrichment factor (EF) > 4). On the other hand, Al, V, Cr, Ni, and Cu show crustal origin in Lake Phewa and the remaining TEs (Mn, Fe, Co, Zn, Cd, and Pb) showed high EF values relative to the crustal elements suggesting potential anthropogenic inputs of the pollutants. The study further indicates that two studied lakes have different potential sources for Mn, Fe, Co, Ni, and Cu regarding TE pollution. A high enrichment of Cd and Pb in high-altitude lake (with less anthropogenic activities) compared to the low-altitude lake (with high anthropogenic activities) indicates atmospheric long-range transportation of the pollutants in remote areas of the Himalayas which might be possible as air masses pass through the industrial areas and deposit in the high altitudes.

Tracing phosphorous distributions in the surficial sediments of two eastern Himalayan high altitude lakes through sequential extraction, multivariate and HYSPLIT back trajectory analyses

Phosphorous (P) fractionation of the surficial sediment of high altitude lakes (HAL) i.e. P.T.Tso and Sella lakes of Arunachal Pradesh State, India were studied with an objective to investigate the phosphorus availability in the environment, nutrient status of the lake and the role of climate change. Moreover, the variation in phosphorous fraction was investigated through mineralogical studies like grain size analysis and X-ray diffraction. The findings revealed that the surficial sediment of lakes are least influenced by anthropogenic sources, since a slight increase in each of the P-Fractions was observed from year 2011 to 2012, except organic P. Loosely sorbed exchangeable phosphorous was found to be slightly high which was due to difference in atmospheric precipitation, which is one of the strong factors in high altitude regions. Decrease in organic fraction of P indicated that lakes became more oligotrophic in nature. Mineralogical investigation shows that illite-montmorillonite and montmorillonite are the main minerals in Sella Lake, whereas montmorillonite and graphite are main minerals in P.T.Tso lake. Factor analysis of seasonal data of P fractionation in surface sediments, along with physical parameters of Sella Lake water indicates three factors for the 2011 data principle factors are pH, EC, oxide-bound and organic P. Factor analysis of P.T.Tso lake water indicates three factors for the 2011 data with principle factors are adsorbed P and authigenic P, pH, oxide-bound P. This study shows that except organic fractions all other fractions are increasing in the following year. It implies that even at such remote high altitude locations P characteristics are changing year to year which sought for further investigation and enables HALs to show the early impacts of climate change related changes. A clear influence of long range transported air pollutants has been found through HYSPLIT back trajectory models which needs to be substantiated through long-term monitoring.

Spatial and seasonal variability of carbonaceous aerosol across Italy

This paper analyses elemental (EC), organic (OC) and total carbon (TC) concentration in PM2.5 and PM10 samples collected over the last few years within several national and European projects at 37 remote, rural, urban, and traffic sites across the Italian peninsula.The purpose of the study is to obtain a picture of the spatial and seasonal variability of these aerosol species in Italy, and an insight into sources, processes and effects of meteorological conditions.OC and EC showed winter maxima and summer minima at urban and rural locations and an opposite behaviour at remote high altitude sites, where they increase during the warm period due to the rising of the Planetary Boundary Layer (PBL). The seasonal averages of OC are higher during winter compared to summer at the rural sites in the Po Valley (from 1.4 to 3.5 times), opposite to what usually occurs at rural locations, where OC increases during the warm period. This denotes the marked influence of urban areas on the surrounding rural environment in this densely populated region.The different types of sites exhibit marked differences in the average concentrations of carbonaceous aerosol and OC/EC ratio. This ratio is less sensitive to atmospheric processing than OC and EC concentrations, and hence more representative of different source types. Remote locations are characterised by the lowest levels of OC and especially EC, with OC/EC ratios ranging from 13 to 20, while the maximum OC and EC concentrations are observed at road-traffic influenced urban sites, where the OC/EC ratio ranges between 1 and 3. The highest urban impacts of OC and EC relative to remote and rural background sites occur in the Po Valley, especially in the city of Milan, which has the highest concentrations of PM and TC and low values of the OC/EC ratio.

Uses of Local Plant Biodiversity among the Tribal Communities of Pangi Valley of District Chamba in Cold Desert Himalaya, India

Pangi Valley is the interior most tribal area in Himachal Pradesh of Northwest Himalaya. An ethnobotanical investigation is attempted to highlight the traditional knowledge of medicinal plants being used by the tribes of Pangi Valley. Various localities visited in the valley 2-3 times in a year and ethnobotanical information was collected through interviews with elderly people, women, shepherds, and local vaids during May 2009 to September 2013. This paper documented 67 plant species from 59 genera and 36 families along with their botanical name, local name, family name, habit, medicinal parts used, and traditional usage, including the use of 35 plants with new ethnomedicinal and other use from the study area for the first time. Wild plants represent an important part of their medicinal, dietary, handicraft, fuel wood, veterinary, and fodder components. These tribal inhabitants and migrants depend on the wild plant resources for food, medicines, fuel, fibre, timber, and household articles for their livelihood security. The present study documents and contributes significant ethnobotanical information from the remote high altitude and difficult region of the world, which remains cut off from rest of the world for 6-7 months due to heavy snowfall.

Are Expedition Medical Kits Too Dangerous to Carry?

If you were to accompany a month‐long expedition into a remote area as a trip physician, you would want to have with you an assortment of medications that would be useful in case of illness or trauma among the expedition members. 1 Your position as a licensed physician would justify the use of prescription medications. If the same adventure travel company were to run the trip without a physician along, should all the medications be left at home? Surprisingly, that's the advice that some adventure travel companies have received from their legal advisors. The thinking seems to be that if you do not have medication, you cannot harm anyone with an adverse drug reaction, or a wrong diagnosis, ignoring the uncomfortable reality that if you do not have medication along it's possible that someone could die, or suffer irreparable harm. The fact that bringing along a group medical kit has even been questioned has largely flown under the radar of the travel medicine world. That is why a study by Pattenden and colleagues 2 in this issue of the Journal of Travel Medicine appropriately highlights an important concern. The authors showed that half of British companies taking clients to remote high altitude destinations did not bring basic drugs to prevent or treat altitude illness. The study did not inquire about other important drugs, but they did discover that several of the companies did not carry group drugs because of fear of liability. An international flight … Corresponding Author: David R. Shlim, MD, Jackson Hole Travel and Tropical Medicine, PO Box 40, Kelly, WY 83011, USA. E‐mail: drshlim{at}wyom.net

Freshwater Biogeography and Limnological Evolution of the Tibetan Plateau - Insights from a Plateau-Wide Distributed Gastropod Taxon (Radix spp.)

BackgroundThe Tibetan Plateau is not only the highest and largest plateau on earth; it is also home to numerous freshwater lakes potentially harbouring endemic faunal elements. As it remains largely unknown whether these lakes have continuously existed during the Last Glacial Maximum (LGM), questions arise as to whether taxa have been able to exist on the plateau since before the latest Pleistocene, from where and how often the plateau was colonized, and by which mechanisms organisms conquered remote high altitude lentic freshwater systems. In this study, species of the plateau-wide distributed freshwater gastropod genus Radix are used to answer these biogeographical questions.Methodology/Principal FindingsBased on a broad spatial sampling of Radix spp. on the Tibetan Plateau, and phylogenetic analyses of mtDNA sequence data, three probably endemic and one widespread major Radix clade could be identified on the plateau. Two of the endemic clades show a remarkably high genetic diversity, indicating a relatively great phylogenetic age. Phylogeographical analyses of individuals belonging to the most widely distributed clade indicate that intra-plateau distribution cannot be explained by drainage-related dispersal alone.Conclusions/SignificanceOur study reveals that Radix spp. persisted throughout the LGM on the Tibetan Plateau. Therefore, we assume the continuous existence of suitable water bodies during that time. The extant Radix diversity on the plateau might have been caused by multiple colonization events combined with a relatively long intra-plateau evolution. At least one colonization event has a Palaearctic origin. In contrast to freshwater fishes, passive dispersal, probably by water birds, might be an important mechanism for conquering remote areas on the plateau. Patterns found in Radix spp. are shared with some terrestrial plateau taxa, indicating that Radix may be a suitable model taxon for inferring general patterns of biotic origin, dispersal and survival on the Tibetan Plateau.

Organochlorine Pesticides (OCPs) in Soils Along the Eastern Slope of the Tibetan Plateau

Soil samples collected from several sites along an altitudinal transect on the eastern slope of the Tibetan Plateau were analyzed for hexachlorobenzenes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs). The results showed that HCHs and DDTs were found in the soil samples from the remote high altitude areas away from source regions, which confirmed the long-range atmospheric transport phenomenon of these organochlorine pesticides (OCPs) insecticides. The OCP concentrations in the soils had a significant negative correlation with altitude; they showed a trend to increase with decreasing altitude, but the increase was not continuous, being interrupted at some moderate-altitude sites on the transect. The distances from the source region, landforms, soil properties, and physical-chemical properties of OCPs were more important than total organic carbon content to the distribution of OCPs in soils disturbed by human activities. An analysis of the compositions of HCH isomers and DDTs revealed predominantly low ratios of CK-HCH to 7-HCH, ranging from 0.06 to 4.79, which suggested current lindane inputs. On the other hand, low p,p'-DDT/ p,p'-DDE and o,p'-DDT/ p,p'-DDT ratios were observed, indicating mainly aged historical DDT residues in the study area.

Atmospheric wet deposition of trace elements to central Tibetan Plateau

To investigate trace elements in wet precipitation over the Tibetan Plateau (TP), a total of 79 event-based precipitation samples were collected from September 2007 to September 2008 at Nam Co Station. Samples were analyzed for concentrations of Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb using inductively coupled plasma-mass spectrometry (ICP-MS). The annual volume-weighted concentrations of elements were generally comparable to other background sites, and much lower than urban areas. The enrichment factors (EF) showed that, in comparison with the Tibetan soils, the wet precipitation had elevated concentrations of Cr, Co, Ni, Cu, Zn, Cd and Pb, probably indicating their anthropogenic origins. Other elements (Al, Fe, Mn and V) with enrichment factor value of <10 may derive mainly from crustal sources. The principal component analysis further confirmed the two different groups of elements in wet deposition samples. The backward trajectories were calculated for each precipitation event using the NOAA HYSPLIT model. The results indicated significant differences of EF for trace elements of anthropogenic origin between the summer monsoon and non-monsoon seasons. The data obtained in the present study indicated that pollutants can affect remote high altitude regions like the Tibetan Plateau through long-range transport, especially in the summer monsoon season.

Journeys to High Altitude—Risks and Recommendations for Travelers with Preexisting Medical Conditions

A literature review was completed using Ovid/ Medline (1950–Present) and Pubmed databases. The following search terms were employed: preexisting medical conditions and altitude, each individual condition and altitude, air travel and preexisting medical conditions, and high altitude medicine. Published articles were used as a source of further references not yielded by the primary search. Textbooks written by recognized experts in the field of high altitude medicine were consulted to source information not available elsewhere. The demographics of adventure travel are shifting. Expanding road, rail, and air networks as well as mechanized mountain lifts have rendered it increasingly possible for people of varying levels of health and fitness to reach remote high altitude destinations (Table 1). 1 High altitude cities and employment sites also attract holidaymakers, workers, and business travelers (Figure 1). 2 Passive ascent to altitude by airplane, automobile, train, hot air balloon, or cable car may result in sudden exposure to altitude without adequate time for acclimatization. View this table: Table 1 Altitude definitions 1 Figure 1 Relative elevations of selected high altitude destinations. The environmental conditions at altitude and the associated hypobaric hypoxia pose a significant physiologic challenge to the human body (Figure 2). Furthermore, many high altitude sojourns include strenuous physical activities such as skiing, hiking, and climbing. Emergencies in remote locations demand that the sick or injured rely on their companions or on their own compromised abilities to access the medical help they need. The conscientious traveler will take steps to gain the knowledge and skills necessary to minimize personal risk. However, many at‐risk travelers remain naive to the health risks of high altitude travel. 3,4 Similarly, physicians should prepare themselves with the knowledge required to advise their patients on safe travel to altitude (Table 2). The need for knowledge and preparedness is especially critical in the case of individuals with … Corresponding Author: Kelly Mieske, BSc, Department of Medicine, Clinical Science Institute, National University of Ireland, Galway, Ireland. E‐mail: k.mieske1{at}nuigalway.ie

Remote European mountain lake ecosystems: regionalisation and ecological status

Summary1. A survey of c. 350 remote high altitude and high latitude lakes from 12 different mountain regions across Europe was undertaken to explore ecosystem variability, climate forcing, environmental conditions and pollution threats at a scale not previously attempted.2. Lakes were sampled for a range of contemporary and sub‐fossil organisms including planktonic crustaceans, rotifers, littoral invertebrates, chironomids, diatoms and cladocerans. Survey and cartographic data were used to determine environmental characteristics at each site. Organic pollutants and trace metal concentrations were measured in the lake sediment.3. A number of separate studies were undertaken which examined the environmental characteristics of the surveyed lakes (climate forcing and chemical composition), distribution of biota relative to local, regional and biogeographical factors and pollution threats (acidification, heavy metals and persistent organic pollutants) to these sensitive ecosystems.4. There is a strong regional element to the way that environmental factors combine (including climate and pollution threats) and the biota responds in mountain lakes across Europe. From a management perspective it is clear that lake classification and the development of useful typologies and assessments of reference conditions should be undertaken at regional rather than pan‐European scales.5. There are some common features across lake districts related to the timing of industrialisation, but the studies carried out on metals, organic pollutants and nitrate deposition indicate that each lake district has distinct pollution threats. Climate warming already affects most of the lake districts and there are considerable uncertainties as to how this will modify conditions in remote European mountain systems.6. The lake district concept goes beyond a geographical construct and merits further theoretical and experimental development as an ecological concept.

Regionalisation of remote European mountain lake ecosystems according to their biota: environmental versus geographical patterns

Summary1. A survey of c. 350 remote high altitude and high latitude lakes from 11 different mountain regions was undertaken to explore species distribution across Europe at a scale not previously attempted.2. Lakes were sampled for planktonic crustaceans, rotifers, littoral invertebrates and sub‐fossil chironomids, diatoms and cladocerans. Each lake was characterised in terms of water chemistry, morphology, catchment attributes and geographical location.3. Separate twinspan analyses were undertaken on diatom, chironomid, planktonic crustacean, littoral invertebrate and cladoceran (chydorids only) data to classify sites according to taxonomic composition. For most datasets there was a spatial component to the classification with distinct geographical groups emerging – Norway and Scotland, Finland and Central/Eastern Europe.4. Constrained ordination methods were employed to examine how species responded to a range of environmental factors, which were aggregated into a series of component groups – proximal environment (the chemical, trophic and physical attributes of the lake), catchment characteristics and geographical location. Several key environmental gradients were identified, which explained significant levels of the variance across several of the biological groups including dissolved organic carbon (chironomids, planktonic crustaceans), temperature (chironomids and littoral invertebrates), chloride/sea‐salt (littoral invertebrates, diatoms and rotifers), lake morphology (all groups), calcium/pH (diatoms), nitrate (chydorids, littoral invertebrates, rotifers and planktonic crustaceans) and fish (littoral invertebrates). In some cases these statistical relationships are likely to represent direct ecological constraints and, in others, it is probable that the environmental variable is acting as a surrogate for some other attribute or process.5. Variance partitioning was undertaken to quantify how much of the variation in each biological group could be uniquely attributed to variables representing the proximal environment, catchment characteristics and geographical location. For most groups the location of the lake tends to explain the greatest variation in species composition across the Lake Districts. The proximal environment was also important but, with the exception of diatoms, secondary to location. Therefore, a strong geographical signal emerged from the analyses. Three distinct limno‐regions were identified; Nordic (Scotland and Norway), Sub‐Arctic (Northern Finland) and Alpine (Pyrenees, the Alps and Eastern Europe ranges).6. Our results have implications for the development of regionalisation schemes based on biological responses to environmental gradients; (i) lake ‘types’ based on environmental factors cannot be extrapolated throughout Europe, even within the relatively narrow gradients found in remote mountain lakes, (ii) biotic response to large‐scale variations in environmental conditions, such as those that could be expected with climate change, is likely to vary according to regions because of the biogeographical differences among them.

Bowen ratio evaporation measurement in a remote montane grassland: Data integrity and fluxes

Summary Evaporation measurements using two Bowen ratio energy balance (BREB) systems in a remote high altitude montane grassland catchment of the Drakensberg Mountains, Cathedral Peak, South Africa are reported on. Various methods of data verification and rejection of inaccurate measured air temperature and water vapour pressure gradients are examined. A theoretical analysis, based on the equivalent temperature, results in data rejection procedures using the measurement of the air temperature profile difference. Data rejection is necessary whenever the Bowen ratio approaches −1, resulting in extremely inaccurate and impossibly large positive or negative sensible heat and latent energy fluxes. Using the simplified energy balance, it is shown that when the Bowen ratio approaches the limit of −1, for which the available energy flux density approaches 0 W m −2 , conditions are pseudoadiabatic and isobaric and that such conditions can be depicted by the wet-bulb temperature isolines of the psychrometric chart. Disregarding evaporation estimates for which the Bowen ratio values are between arbitrarily chosen values remedies the problem to some extent. With this method, daily total evaporation may be reasonable but 20-min values unreasonable during mainly early morning and late afternoon periods. A more sensitive and dynamic approach is used to prevent BREB data from being excluded unnecessarily and to prevent rogue values escaping detection. Once the rejection procedures were applied, the 20-min BREB latent energy flux estimates compared well with measurements from a weighing lysimeter adjacent the site. Three methods were used to estimate the exchange coefficient K which allowed flux estimation for when BREB data are invalid or lacking. One method involved calculating K from wind speed only and the second method was based on the MOST-dependent temperature-variance method for which the 20-min standard deviation of 1-Hz air temperature data were used. From independent measurements of sensible heat H and latent energy LE , a time-invariant exchange coefficient K was also determined from measurements of the air temperature profile difference. These methods were used when there were invalid water vapour pressure data due to condensation in the hoses or problems with the cooled dew point mirror or when the fine-wire thermocouples were damaged or when there were unreliable estimates of the air temperature gradient. The time-invariant value for K used in one of the methods, 0.239 m 2 s −1 , was confirmed for a mixed grassland catchment using independent eddy covariance and surface-layer scintillometer measurements of H and Bowen ratio measurements of the air temperature profile difference.

The contribution of biological particles to observed particulate organic carbon at a remote high altitude site

Although a significant fraction of atmospheric particulate mass is organic carbon, the sources of particulate organic carbon (POC) are not always apparent. One potential source of atmospheric POC is biological particles, such as bacteria, pollen, and fungal spores. Measurements of POC and biological particles, including bacteria, fungal spores, and pollen, were made as part of the Storm Peak Aerosol and Cloud Characterization Study in Steamboat Springs, CO in March–April 2008. Biological particles were identified and characterized using several methods. The results suggest that biological particles could account for an average of 40% of the organic carbon mass in particles with aerodynamic diameters less than 10 μm. These estimates of POC mass from biological particles are highly uncertain; however, the results suggest that biological particles could be a significant source of organic aerosol in the background continental atmosphere and further observations are needed to better constrain these estimates.

Isolation of Bacteria from Remote High Altitude Andean Lakes Able to Grow in the Presence of Antibiotics

High altitude Andean lakes are placed in Puna desert over 4400 above sea level. Completely isolated, they are exposed to extreme environmental factors like high levels of salinity, UV radiation and heavy metals and low concentrations of phosphorus. Nevertheless, they are the habitat of enormous populations of three flamingo species that migrate among these Lakes. Previous reports have determined that bacteria isolated from these environments present high levels of resistance to antibiotics. The aim of this work was to determine the diversity of antibiotic resistant bacteria in water from Andean Lakes and their connection with flamingo enteric biota. Bacteria from water and birds faeces from high altitude Lakes: Laguna (L.) Aparejos, L. Negra, L. Vilama and L. Azul (all are located between 4,200 and 4,600 m altitude) were isolated by plating in five different Antibiotics (ampicillin, 100 microg ml(-1); chloramphenicol, 170 microg ml(-1); colistin , 20 microg ml(-1); erythromycin, 50 microg ml(-1) and tetracycline 50 microg ml(-1)). 56 bacteria were isolated and identified by 16 S rDNA sequencing. Antibiotic resistance profiles of isolated bacteria were determined for 22 different antibiotics. All identified bacteria were able to growth in multiple ATBs. Colistin, ceftazidime, ampicillin/sulbactam, cefotaxime, cefepime, cefalotin, ampicillin and erythromycin were the most distributed resistances among the 56 tested bacteria. The current results demonstrated that antibiotic resistance was abundant and diverse in high altitude Lakes. Also the present article indicates some useful patents regarding the isolation of bacteria able to grow in the present of antibiotics.

Tibet Field Camp as a ‘Roof of the World’ Capstone Experience for Earth Science Majors

As fieldwork is an essential experiential learning component of any Earth Science education there is arguably nowhere better to run such an exercise than in a spectacular geological setting in Tibet. In June 2006, a group of 33 students from highly urbanized backgrounds travelled to several remote high altitude locales, in order to examine some of the best geology on Earth. The result was one of the most successful field learning exercises for both students and staff in the history of our department.