SARS-CoV-2 Transmission during High-Altitude Field Studies

Grimm, Mirjam, Lucie Ziegler, Annina Seglias, Maamed Mademilov, Kamila Magdieva, Gulzada Mirzalieva, Aijan Taalaibekova, Simone Suter, Simon R. Schneider, Fiona Zoller, Vera Bissig, Lukas Reinhard, Meret Bauer, Julian Müller, Tanja L. Ulrich, Arcangelo F. Carta, Patrick R. Bader, Konstantinos Bitos, Aurelia E. Reiser, Benoit Champigneulle, Damira Ashyralieva, Philipp M. Scheiwiller, Silvia Ulrich, Talant M. Sooronbaev, Michael Furian, and Konrad E. Bloch. SARS-CoV-2 Transmission during High-Altitude Field Studies. High Alt Med Biol. 00:00-00, 2024. Background: Throughout the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic, virus transmission during clinical research was of concern. Therefore, during high-altitude field studies performed in 2021, we took specific COVID-19 precautions and investigated the occurrence of SARS-CoV-2 infection. Methods: From May to September 2021, we performed studies in patients with chronic obstructive pulmonary disease (COPD) and in healthy school-age children in Kyrgyzstan in high-altitude facilities at 3,100 m and 3,250 m and at 760 m. The various implemented COVID-19 safety measures included systematic SARS-CoV-2 rapid antigen testing (RAT). Main outcomes were SARS-CoV-2-RAT-positive rate among participants and staff at initial presentation (prevalence) and SARS-CoV-2-RAT-positive conversion during and within 10 days after studies (incidence). Results: Among 338 participants and staff, SARS-CoV-2-RAT-positive prevalence was 15 (4.4%). During mean ± SD duration of individual study participation of 3.1 ± 1.0 day and within 10 days, RAT-positive conversion occurred in 1/237(0.4%) participants. Among staff working in studies for 31.5 ± 29.3 days, SARS-CoV-2-RAT-positive conversion was 11/101(10.9%). In all 338 individuals involved in the studies over the course of 15.6 weeks, the median SARS-CoV-2-RAT-positive incidence was 0.00%/week (quartiles 0.00; 0.64). Over the same period, the median background incidence among the total Kyrgyz population of 6,636 million was 0.06%/week (0.03; 0.11), p = 0.013 (Wilcoxon rank sum test). Conclusions: Taking precautions by implementing specific safety measures, SARS-CoV-2 transmission during clinical studies was very rare, and the SARS-CoV-2 incidence among participants and staff was lower than that in the general population during the same period. The results are reassuring and may help in decision-making on the conduct of clinical research in similar settings.

From laboratory to mountaintop: Creating an artificial aurora in the late nineteenth century

There existed a tradition of mimetic experimentation in the late nineteenth century, whereby morphologists sought to scale down sublime natural phenomena to tabletop devices in the laboratory. Experimenters constructed analogs of the aurora, attempting to replicate the colors and forms of the phenomenon with discharge tube experiments and electrical displays, which became popular spectacles at London's public galleries. This paper analyses a closely allied but different kind of imitation. Between 1872 and 1884, Professor Karl Selim Lemström (1838-1904) attempted to reproduce the aurora borealis in all of its complexity atop four mountains in northern Finland. Crucially, his "artificial aurora" was to materialize at the same scale as the original phenomenon and in its natural habitat in the polar atmosphere. With his experiment Lemström hoped to uncover the workings of the aurora and the electrical currents that he believed were always present within the atmosphere; his epistemological framework was one of learning by making. This paper sheds light on the broader problem of what it meant to authentically replicate a phenomenon that remained largely enigmatic, and, most importantly, how this replication could be verified. This prompts a discussion as to whether model experiments needed only to appear visually similar to the objects they purported to imitate, were required to preserve their form, or needed to be materially identical in order to the original to be identified as legitimate "reproductions" in the late nineteenth century.

Elevational Goldilocks zone underlies the exceptional diversity of a large lizard radiation (Liolaemus; Liolaemidae)

Mountains are among the most biodiverse regions on the planet, and how these landforms shape diversification through the interaction of biological traits and geo-climatic dynamics is integral to understanding global biodiversity. In this study, we investigate the dual roles of climate change and mountain uplift on the evolution of a hyper-diverse radiation, Liolaemus lizards, with a spatially explicit model of diversification using a reconstruction of uplift and paleotemperature in central and southern South America. The diversification model captures a hotspot for Liolaemus around 40°S in lineages with low-dispersal ability and narrow niche breadths. Under the model, speciation rates are highest in low latitudes (<35°S) and mid elevations (~1,000 m), while extinction rates are highest at higher latitudes (>35°S) and higher elevations (>2,000 m). Temperature change through the Cenozoic explained variation in speciation and extinction rates through time and across different elevational bands. Our results point to the conditions of mid elevations being optimal for diversification (i.e., Goldilocks Zone), driven by the combination of (1) a complex topography that facilitates speciation during periods of climatic change, and (2) a relatively moderate climate that enables the persistence of ectothermic lineages and buffers species from extinction.

Rewarming from unwitnessed hypothermic cardiac arrest with good neurological recovery using extracorporeal membrane oxygenation

A 26-year-old man, who was training in bad weather for a mountain ultramarathon, became hypothermic after running for 4 h. He deteriorated and was unable to continue. His running partner went for help. The man suffered an unwitnessed hypothermic cardiac arrest. The on-site management and evacuation are described and included the use of intermittent cardiopulmonary resuscitation and a mechanical device during transport. The patient was successfully resuscitated and rewarmed by Extracorporeal Membrane Oxygenation (ECMO) after more than 2 h of cardiopulmonary resuscitation. After 14 h of ECMO support and five days of ventilation, the patient subsequently made a good neurological recovery. At hospital discharge, he had normal cerebral function, and an improving peripheral polyneuropathy affecting distal limbs, with paraesthesia in both feet and reduced coordination and fine motor skills in both hands.

What Is the Value of a "Mountain Product" Claim? A Ranking Conjoint Experiment on Goat's Milk Yoghurt

Rural development is complex in marginal and disadvantaged areas, such as mountains, which impose high labour costs and restrict farmers in their choices of crop and livestock. To recognise this problem, the European Union regulates the use of the optional quality term "Mountain product" on the label. Consumers may recognise this label and be more willing to pay for it, resulting in higher revenues for producers using it. This study estimates the willingness to pay (WTP) for a mountain quality label. This WTP is then compared to that of functional and nutrition claims. For this purpose, we used a ranking conjoint experiment, using goat's milk yoghurt-a typical mountain product-as a case study. Using a rank-ordered logit, we show that mountain quality labels generate a significant WTP, higher than that of functional claims. WTP differs by the demographic profile of the consumer. The study provided useful insights about the combination of the mountain quality label with different attributes. However, future studies are needed to adequately understand the potential of mountain certification as a supporting tool for farmers in marginal areas and for rural development.

Larval development and poor trophic resource availability: Local adaptations and plasticity in a widespread amphibian species

Theory predicts that, in organisms with complex life cycles, if the earlier-stage limiting factor induces weak later-stage phenotypes, the development of the later-stage trait should evolve to reduce carry-over effects. Local adaptations could thus favour decoupling of later stages. However, decoupling is not always possible. In this study, we used a widespread amphibian, the European fire salamander (Salamandra salamandra), to assess the role of local adaptations to environmental stressful conditions experienced at the larval stage. We exposed 150 larvae from different altitudes to two conditions: rich food and poor food condition. Conditions in early life stages can affect an individual's traits, either as a direct effect or mediated through outcomes in successive life stages. To distinguish between effects of rearing conditions and local adaptation, we searched for a causal model. The causal model detected effects of both food treatment and population origin (altitude) on all life stages. Larvae reared under rich food condition metamorphosed earlier, had higher growth rates and reached smaller size at metamorphosis. Significant differences occurred between larvae of different origin: low-altitude individuals performed poorly under the poor food treatment. Moreover, larvae from higher altitudes were slower with rich food and faster with poor food compared to those from lower altitudes. Our results underline that environmental conditions and local adaptation can interplay in determining the plasticity of larval stages, still adaptations can maximize the growth efficiency of early stages in oligotrophic environments, leading to divergent pathways across populations and environmental conditions.

Remote Sensing Application in Mountainous Environments: A Bibliographic Analysis

Advancement in remote sensing platforms, sensors, and technology has significantly improved the assessment of hard-to-access areas, such as mountains. Despite these improvements, Africa lags in terms of research work published. This is of great concern as the continent needs more research to achieve sustainable development. Therefore, this study applied a bibliometric analysis of the annual production of publications on the application of remote sensing methods in mountainous environments. In total, 3849 original articles between 1973 and 2021 were used, and the results indicate a steady growth in publications from 2004 (n = 26) to 2021 (n = 504). Considering the source journals, Remote Sensing was the top-ranked, with 453 total publications. The University of the Chinese Academy of Sciences was the highest-ranking affiliation, with 217 articles, and China produced the highest number of publications (n = 217). Keywords used between 1973 and 1997, such as "Canada", "alps", and "GIS", metamorphosed into "remote sensing" between 1998 and 2021. This metamorphosis indicates a change in the areas of interest and an increase in the application of remote sensing methods. Most studies were conducted in the Global North countries, and a few were published in low-impact journals within the African continent. This study can help researchers and scholars better understand the progress and intellectual structure of the field and future research directions in the application of remote sensing methods in mountainous environments.

Seasonal Oxy-Inflammation and Hydration Status in Non-Elite Freeskiing Racer: A Pilot Study by Non-Invasive Analytic Method

Freeskiing is performed in an extreme environment, with significant physical effort that can induce reactive oxygen species (ROS) generation and dehydration. This study aimed to investigate the evolution of the oxy-inflammation and hydration status during a freeskiing training season with non-invasive methods. Eight trained freeskiers were investigated during a season training: T0 (beginning), T1-T3 (training sessions), and T4 (after the end). Urine and saliva were collected at T0, before (A) and after (B) T1-T3, and at T4. ROS, total antioxidant capacity (TAC), interleukin-6 (IL-6), nitric oxide (NO) derivatives, neopterin, and electrolyte balance changes were investigated. We found significant increases in ROS generation (T1A-B +71%; T2A-B +65%; T3A-B +49%; p < 0.05-0.01) and IL-6 (T2A-B +112%; T3A-B +133%; p < 0.01). We did not observe significant variation of TAC and NOx after training sessions. Furthermore, ROS and IL-6 showed statistically significant differences between T0 and T4 (ROS +48%, IL-6 +86%; p < 0.05). Freeskiing induced an increase in ROS production, which can be contained by antioxidant defense activation, and in IL-6, as a consequence of physical activity and skeletal muscular contraction. We did not find deep changes in electrolytes balance, likely because all freeskiers were well-trained and very experienced.

Changes in microbial community structure and functioning with elevation are linked to local soil characteristics as well as climatic variables

Mountain forests are important carbon stocks and biodiversity hotspots but are threatened by increased insect outbreaks and climate-driven forest conversion. Soil microorganisms play an eminent role in nutrient cycling in forest habitats and form the basis of soil food webs. Uncovering the driving factors shaping microbial communities and functioning at mountainsides across the world is of eminent importance to better understand their dynamics at local and global scales. We investigated microbial communities and their climatic and local soil-related drivers along an elevational gradient (800-1700 m asl) of primary forests at Changbai Mountain, China. We analyzed substrate-induced respiration and phospholipid fatty acids (PLFA) in litter and two soil layers at seven sites. Microbial biomass (C_mic) peaked in the litter layer and increased towards higher elevations. In the litter layer, the increase in C_mic and in stress indicator ratios was negatively correlated with Ca concentrations indicating increased nutritional stress in high microbial biomass communities at sites with lower Ca availability. PLFA profiles in the litter layer separated low and high elevations, but this was less pronounced in soil, suggesting that the litter layer functions as a buffer for soil microbial communities. Annual variations in temperature correlated with PLFA profiles in all three layers, while annual variations in precipitation correlated with PLFA profiles in upper soil only. Furthermore, the availability of resources, soil moisture, Ca concentrations, and pH structured the microbial communities. Pronounced changes in C_mic and stress indicator ratios in the litter layer between pine-dominated (800-1100 m) and spruce-dominated (1250-1700 m) forests indicated a shift in the structure and functioning of microbial communities between forest types along the elevational gradient. The study highlights strong changes in microbial community structure and functioning along elevational gradients, but also shows that these changes and their driving factors vary between soil layers. Besides annual variations in temperature and precipitation, carbon accumulation and nitrogen acquisition shape changes in microbial communities with elevation at Changbai Mountain.

Mosquito (Diptera: Culicidae) Diversity and Community Structure in Doi Inthanon National Park, Northern Thailand

Urbanization and human activities create new suitable aquatic habitats for the immature stages of mosquitoes in many countries. This also applies to Doi Inthanon National Park in northern Thailand, which is named for the highest mountain in the country. Despite its popularity, there is no information regarding mosquito diversity and community structure in the different ecosystems of the park. Monthly collections of immature stages from various habitats were conducted from August 2004 to December 2005 using dipping and sucking methods. The specimens collected from each habitat were reared to adults and identified based on their morphology. Diversity parameters and community structure were statistically analyzed. A total of 140 species (3795 specimens) belonging to 15 genera were identified. Among these, four genera (Culex, Aedes, Anopheles, and Uranotaenia) had high species richness, each represented by 48, 27, 19, and 15 species, respectively. Aedes albopictus was the most relatively abundant species, representing 6.7% of the total number of captured specimens, followed by Tripteroides aranoides (5.6%) and Cx. mimulus (5%). Species richness in natural habitats was significantly higher than in artificial containers. Species richness and abundance were highest in the rainy season. In comparison to agricultural areas and villages, mosquito diversity was found to be higher in forest areas. Ground pools, stream pools, rock pools, bamboo stumps, bamboo internode, and rice fields were the most preferred natural habitats. The results indicate that Doi Inthanon National Park has a high mosquito diversity. Each species exhibits differences in abundance and distribution in different habitats, which is useful information for planning conservation measures and vector control in the park.

Telemedicine for Patient Management in Remote Areas and Underserved Populations

Access to care services in remote areas is challenging. The use of telemedicine technology in these areas facilitates access to health care. This study aimed to summarize the current research on telemedicine in remote areas such as mountains and forests. A systematic search was conducted in databases including Medline (through PubMed), Scopus, IEEE Xplore Digital Library, and ISI Web of Science to identify relevant studies published until May 12, 2021. Screening of retrieved articles for selection and inclusion in the study was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes extension for Scoping Reviews (PRISMA-ScR) checklist. A total of 807 articles were identified after removing duplicates, from which 20 studies meeting our inclusion criteria were selected. Challenges, opportunities, and equipment required to use telemedicine in remote areas were extracted from the selected studies. The results revealed that telemedicine implementation in remote areas had many challenges, including harsh weather conditions, Internet connectivity problems, difficult equipment transportation, and ethical issues. Telemedicine also has many benefits, such as cost and time savings for patients, improving patients' quality of life, and improving patient satisfaction. Telemedicine for inhabitants of forested and mountainous areas facilitates rapid access to health care and enhances patient satisfaction. Distinguishing advantages and barriers as well as reducing restrictions will have an essential role in accelerating the use of this technology.

[When the mountain heals the souls of sick children]

The association À Chacun Son Everest ! created in 1994 by Christine Janin, offers stays in the Chamonix valley (74) to children who have been through the ordeal of cancer. Accompanied by volunteer carers and the team at Chalet Vallot, they discover the mountains, their magnificence and their strength. The activities planned by the association, in contact with this grandiose environment, allow them to regain their self-confidence and to rebuild their lives after the harshness of the disease.

Strategic protection of landslide vulnerable mountains for biodiversity conservation under land-cover and climate change impacts

Landslides are triggered more often by human-induced changes, such as deforestation, infrastructure building, and increasing precipitation extremes, because of climate change. The huge economic and societal loss calls for a more cost-effective way to reduce risks and ensure sustainable development. Land-cover and land-use changes not only increase landslide susceptibility but also drive habitat loss and species extinctions. The high spatial overlap between landslide susceptibility and biodiversity in mountains provides an opportunity to achieve co-benefits in conservation and development. The identification of vulnerable mountains with both high biodiversity and landslide susceptibility prioritizes the regions for expansion of protected areas, forest conservation, and restoration, providing a nature-based solution to mitigate landslide risks through the protection of natural habitat.

Natural disasters impose huge uncertainty and loss to human lives and economic activities. Landslides are one disaster that has become more prevalent because of anthropogenic disturbances, such as land-cover changes, land degradation, and expansion of infrastructure. These are further exacerbated by more extreme precipitation due to climate change, which is predicted to trigger more landslides and threaten sustainable development in vulnerable regions. Although biodiversity conservation and development are often regarded as having a trade-off relationship, here we present a global analysis of the area with co-benefits, where conservation through expanding protection and reducing deforestation can not only benefit biodiversity but also reduce landslide risks to human society. High overlap exists between landslide susceptibility and areas of endemism for mammals, birds, and amphibians, which are mostly concentrated in mountain regions. We identified 247 mountain ranges as areas with high vulnerability, having both exceptional biodiversity and landslide risks, accounting for 25.8% of the global mountainous areas. Another 31 biodiverse mountains are classified as future vulnerable mountains as they face increasing landslide risks because of predicted climate change and deforestation. None of these 278 mountains reach the Aichi Target 11 of 17% coverage by protected areas. Of the 278 mountains, 52 need immediate actions because of high vulnerability, severe threats from future deforestation and precipitation extremes, low protection, and high-population density and anthropogenic activities. These actions include protected area expansion, forest conservation, and restoration where it could be a cost-effective way to reduce the risks of landslides.

Excess mortality in Mountain Areas of Emilia Romagna Region during the first months of SARS-CoV-2 pandemic: a "canary in the coal mine"?

BACKGROUND

Because of their remoteness, Mountain Communities (MC) have been considered at advantage when dealing with infectious diseases. However, earlier reports have identified MC among the hotspots for early spreading of COVID-19 pandemic.

METHODS

Crude mortality rates (CMR) and Excess mortality rates (EMR) were calculated for 97 municipalities from MC in the Emilia Romagna Region, and resulting estimates were compared to the Parent Provinces. Notification and mortality rates for COVID-19 were also retrieved, and correlated with EMR estimates.

RESULTS

During 2020, a CMR of 150.3/100,000 (95% Confidence Interval [95%CI] 117-185.4) was identified, with substantial heterogeneities between the 8 provinces of Emilia Romagna Region that were included in the analyses. A pooled EMR of +20.3% (95%CI 10.6-30.1) for MC and 19.9% (95%CI 9.5-30.3) was identified. The monthly estimates were quite heterogenous across the various provinces, ranging between -79.7% and +307.4% during the assessed timeframe. Higher estimates were identified in the months of March and April in MC, and during the months of April and May for Parent Provinces. In bivariate analysis, EM in MC was positively correlated with estimates in the parent province (Spearman's r = 0.201, p = 0.049), and also with notification rates for COVID- (i.e. Piacenza, Parma, Reggio Emilia, Modena, Bologna, Ravenna, Rimini, and Forlì Cesena) (r = 0.225, p = 0.045), and particularly with mortality rates for COVID-19 at provincial level (r = 0.372, p < 0.001).

CONCLUSIONS

In summary, the study highlights that small geographical and population size, along with remoteness, did not play a substantial advantage for MC against the spread and mortality rate of COVID-19. On the other hand, as the surge of EM in MC anticipated a similar habit in Parent Provinces of several weeks, improved surveillance interventions are also urgently in need. (www.actabiomedica.it).

Habitat Use and Activity Patterns of Mammals and Birds in Relation to Temperature and Vegetation Cover in the Alpine Ecosystem of Southwestern China with Camera-Trapping Monitoring

Simple Summary

The Wolong National Nature Reserve in Sichuan province covers a unique mountainous ecosystem located on the eastern border of the Tibetan Plateau in China. We applied a popular non-invasive observational method, i.e., infrared-triggered camera trapping, to gain thousands of photographs of wildlife to monitor biodiversity over three years. Combined with data on the local abiotic factors, our integrative statistical analysis identified the key environmental drivers, i.e., temperature and vegetation, affecting the distribution and abundance of mammals and birds in the reserve. All species were classified into three main types by their tolerance of or fondness for different environmental conditions. The detectability of each species by camera trapping was quantified and ranked to provide insights on each species’ relative abundance in the area.

Abstract

The high-altitude ecosystem of the Tibetan Plateau in China is a biodiversity hotspot that provides unique habitats for endemic and relict species along an altitudinal gradient at the eastern edge. Acquiring biodiversity information in this area, where the average altitude is over 4000 m, has been difficult but has been aided by recent developments in non-invasive technology, including infrared-triggered camera trapping. We used camera trapping to acquire a substantial number of photographic wildlife records in Wolong National Nature Reserve, Sichuan, China, from 2013 to 2016. We collected information of the habitat surrounding the observation sites, resulting in a dataset covering 37 species and 12 environmental factors. We performed a multivariate statistical analysis to discern the dominant environmental factors and cluster the mammals and birds of the ecosystem in order to examine environmental factors contributing to the species’ relative abundance. Species were generalized into three main types, i.e., cold-resistant, phyllophilic, and thermophilic, according to the identified key environmental drivers (i.e., temperature and vegetation) for their abundances. The mammal species with the highest relative abundance were bharal (Pseudois nayaur), Moupin pika (Ochotona thibetana), and Himalayan marmot (Marmota himalayana). The bird species with highest relative abundance were snow partridge (Lerwa lerwa), plain mountain finch (Leucosticte nemoricola), Chinese monal (Lophophorus lhuysii), and alpine accentor (Prunella collaris).

Incidence of exercise-associated hyponatremia during a high-altitude 161-km ultramarathon

[Purpose]

Exercise-associated hyponatremia (EAH) is a well-known condition among endurance athletes at low altitudes. The incidence of EAH during ultramarathons at high altitudes warrants further investigation. This prospective observational study was conducted on the participants of the Leadville Trail 100 run, a 161-km race held at a high altitude (2,800 m-3,840 m).

[Methods]

Venous blood samples were collected before and immediately after the race. The participants completed an electronic survey after the race. Our main outcome measure was the post-race serum sodium ([Na⁺]) level.

[Results]

Of the 672 athletes who started the race, 351 (52%) successfully completed the event within the 30-hour cut-off. Post-race blood samples were collected from 84 runners (66 finishers). Both pre- and post-race blood samples were collected from 37 participants. Twenty percent of the post-race participants had EAH. Only one post-race participant had a [Na⁺] level of <130 mmol/L. All participants with EAH were asymptomatic. One participant had an abnormal pre-race [Na⁺] level (134 mmol/L). Female participants had a significantly higher rate of EAH than male participants (40% vs. 16%; p=0.039). Age, body mass index, weight changes, race completion status, nonsteroidal anti-inflammatory drug use, and urine specific gravity were not associated with the development of EAH. Lower postrace [Na⁺] levels were associated with higher serum creatine kinase values (R²=0.1, p<0.005).

[Conclusion]

High altitude (3,840 m peak) does not appear to enhance the incidence of EAH after an ultramarathon footrace. This suggests that ambient temperature (low temperatures reduce risk), sex (female predilection), endurance running, and overhydration are more prominent risk factors for EAH than high altitude.

Comparison of the distribution and phenology of Arctic Mountain plants between the early 20th and 21st centuries

Arctic plants are adapted to climatic variability, but their long-term responses to warming remain unclear. Responses may occur by range shifts, phenological adjustments in growth and reproduction, or both. Here, we compare distribution and phenology of 83 arctic and boreal mountain species, sampled identically in the early 20th (1917-1919) and 21st centuries (2017-2018) from a region of northern Sweden that has warmed significantly. We test two compensatory hypotheses to high-latitude warming-upward shifts in distribution, and earlier or extended growth and reproduction. For distribution, we show dramatic upward migration by 69% of species, averaging 6.1 m per decade, especially boreal woodland taxa whose upward expansion has reduced arctic montane habitat by 30%. Twenty percent of summit species showed distributional shifts but downward, especially moisture-associated snowbed flora. For phenology, we detected wide inter-annual variability in the onset of leafing and flowering in both eras. However, there was no detectable change in growing-season length, relating to two mechanisms. First, plot-level snow melt data starting in 1917 demonstrated that melt date, rather than vernal temperatures, better predicts plant emergence, with snow melt influenced by warmer years having greater snowfall-warmer springs did not always result in earlier emergence because snowbeds can persist longer. Second, the onset of reproductive senescence between eras was similar, even when plant emergence was earlier by a month, possibly due to intensified summer heat stress or hard-wired 'canalization' where senescence occurs regardless of summer temperature. Migrations in this system have possibly buffered arctic species against displacement by boreal expansion and warming, but ongoing temperature increases, woody plant invasion, and a potential lack of flexibility in timing of senescence may foreshadow challenges.

Impact of Climate Change on Health and Well-Being of People in Hindu Kush Himalayan Region: A Narrative Review

Climate change and variability affect virtually everyone and every region of the world but the effects are nowhere more prominent than in mountain regions and people living therein. The Hindu Kush Himalayan (HKH) region is a vast expanse encompassing 18% of the world’s mountainous area. Sprawling over 4.3 million km², the HKH region occupies areas of eight countries namely Nepal, Bhutan, Afghanistan, Bangladesh, China, India, Myanmar, and Pakistan. The HKH region is warming at a rate higher than the global average and precipitation has also increased significantly over the last 6 decades along with increased frequency and intensity of some extreme events. Changes in temperature and precipitation have affected and will like to affect the climate-dependent sectors such as hydrology, agriculture, biodiversity, and human health. This paper aims to document how climate change has impacted and will impact, health and well-being of the people in the HKH region and offers adaptation and mitigation measures to reduce the impacts of climate change on health and well-being of the people. In the HKH region, climate change boosts infectious diseases, non-communicable diseases (NCDs), malnutrition, and injuries. Hence, climate change adaptation and mitigation measures are needed urgently to safeguard vulnerable populations residing in the HKH region.

The complete chloroplast genome sequence of endangered plant Trachycarpus nanus (Arecaceae)

Trachycarpus nanus is an endangered plant that is endemic to southwest of China. In the present study, the complete chloroplast genome of this species was assembled and characterized using whole genome next-generation sequencing. The complete chloroplast genome showed a circular genome of 158,713 bp size with 36.6% GC content. The genome is of typical structure and contain a pair of inverted repeat (IR) regions with 27,240 bp, separated by one large single-copy (LSC) with 86,395 bp, and one small single-copy (SSC) regions with 17,838 bp. The genome contained 132 genes, including 86 protein-coding genes, 8 rRNA genes and 38 tRNA genes. A phylogenetic tree reconstructed based on 21 chloroplast genomes reveals that Trachycarpus nanus is most related with Chamaerops humilis. The information provides important genetic basis for the species’ future studies on phylogenetic and utilization.

Global and country-level estimates of human population at high altitude

Estimates of the global population of humans living at high altitude vary widely, and such data at the country level are unavailable. Herein, we use a geographic information system (GIS)-based approach to quantify human population at 500-m elevation intervals for each country. Based on georeferenced data for population (LandScan Global 2019) and elevation (Global Multiresolution Terrain Elevation Data), 500.3 million humans live at ≥1,500 m, 81.6 million at ≥2,500 m, and 14.4 million at ≥3,500 m. Ethiopia has the largest absolute population at ≥1,500 m and ≥2,500 m, while China has the greatest at ≥3,500 m. Lesotho has the greatest percentage of its population above 1,500 m, while Bolivia has the greatest at ≥2,500 m and ≥3,500 m. High altitude presents a myriad of environmental stresses that provoke physiological responses and adaptation, and consequently impact disease prevalence and severity. While the majority of high-altitude physiology research is based upon lowlanders from western, educated, industrialized, rich, and democratic countries ascending to high altitude, the global population distribution of high-altitude residents encourages an increased emphasis on understanding high-altitude physiology, adaptation, epidemiology, and public health in the ∼500 million permanent high-altitude residents.

Local Small Ruminant Grazing in the Monti Foy Area (Italy): The Relationship Between Grassland Biodiversity Maintenance and Added-Value Dairy Products

The literature indicates that grazing small ruminants, when adequately managed, contributes to grassland biodiversity maintenance. On the other hand, milk and cheese from grazing animals show higher nutritional and aromatic quality than those from stall-fed animals. The relationship between the two issues has rarely been addressed. This article provides information for a discussion of this relationship. First, two case studies are reported. Local breeds of small ruminants fed by grazing on pastures within the Special Area of Conservation "Monti Foy" in the Northwestern Basilicata region (Italy), with a stocking rate of 4.0 LU ha^-1 year^-1, showed the best effectiveness for the maintenance of grassland botanical biodiversity. Milk and cheese from pasture-fed goats showed higher contents of beneficial fatty acids, phenols, and vitamins A and E; higher degree of antioxidant protection; and richer volatile compound profiles, in particular for terpenes content. Finally, some recommendations for the management of grazing systems in similar mountain areas are offered, including a viable approach for land managers to preserve the grassland biodiversity of pastures and provide high-quality products that are valuable both for their nutritional quality and for their contribution to the economic sustainability of mountain communities.

Montane forest productivity across a semiarid climatic gradient

High-elevation montane forests are disproportionately important to carbon sequestration in semiarid climates where low elevations are dry and characterized by low carbon density ecosystems. However, these ecosystems are increasingly threatened by climate change with seasonal implications for photosynthesis and forest growth. As a result, we leveraged eddy covariance data from six evergreen conifer forest sites in the semiarid western United States to extrapolate the status of carbon sequestration within a framework of projected warming and drying. At colder locations, the seasonal evolution of gross primary productivity (GPP) was characterized by a single broad maximum during the summer that corresponded to snow melt-derived moisture and a transition from winter dormancy to spring activity. Conversely, winter dormancy was transient at warmer locations, and GPP was responsive to both winter and summer precipitation such that two distinct GPP maxima were separated by a period of foresummer drought. This resulted in a predictable sequence of primary limiting factors to GPP beginning with air temperature in winter and proceeding to moisture and leaf area during the summer. Due to counteracting winter (positive) and summer (negative) GPP responses to warming, leaf area index and moisture availability were the best predictors of annual GPP differences across sites. Overall, mean annual GPP was greatest at the warmest site due to persistent vegetation photosynthetic activity throughout the winter. These results indicate that the trajectory of this region's carbon sequestration will be sensitive to reduced or delayed summer precipitation, especially if coupled to snow drought and earlier soil moisture recession, but summer precipitation changes remain highly uncertain. Given the demonstrated potential for seasonally offsetting responses to warming, we project that decadal semiarid montane forest carbon sequestration will remain relatively stable in the absence of severe disturbance.

Solar UV Radiation in the Tropics: Human Exposure at Reunion Island (21° S, 55° E) during Summer Outdoor Activities

Reunion Island is a popular tourist destination with sandy beaches, an active volcano (Piton de la Fournaise), and Piton des Neiges, the highest and most dominant geological feature on the island. Reunion is known to have high levels of solar ultraviolet radiation (UVR) with an ultraviolet index (UVI) which can reach 8 in winter and 16 in summer (climatological conditions). UVR has been linked to skin cancer, melanoma, and eye disease such as cataracts. The World Health Organization (WHO) devised the UVI as a tool for expressing UVR intensity. Thresholds ranging from low (UVI 1-2) to extreme (UVI > 11) were defined depending on the risk to human health. The purpose of the study was to assess UVR exposure levels over three of the busiest tourist sites on the island. UVR was measured over several hours along popular hiking trails around Piton de la Fournaise (PDF), Piton des Neiges (PDN), and St-Leu Beach (LEU). The results were compared with those recorded by the local UV station at Saint-Denis. In addition, cumulative standard erythemal dose (SED) was calculated. Results showed that UVI exposure at PDF, PDN, and LEU were extreme (>11) and reached maximum UVI levels of 21.1, 22.5, and 14.5, respectively. Cumulative SEDs were multiple times higher than the thresholds established by the Fitzpatrick skin phototype classification. UVI measurements at the three study sites showed that Reunion Island is exposed to extreme UVR conditions. Public awareness campaigns are needed to inform the population of the health risks related to UVR exposure.

Best environmental predictors of breeding phenology differ with elevation in a common woodland bird species

Temperatures in mountain areas are increasing at a higher rate than the Northern Hemisphere land average, but how fauna may respond, in particular in terms of phenology, remains poorly understood. The aim of this study was to assess how elevation could modify the relationships between climate variability (air temperature and snow melt-out date), the timing of plant phenology and egg-laying date of the coal tit (Periparus ater). We collected 9 years (2011-2019) of data on egg-laying date, spring air temperature, snow melt-out date, and larch budburst date at two elevations (~1,300 m and ~1,900 m asl) on a slope located in the Mont-Blanc Massif in the French Alps. We found that at low elevation, larch budburst date had a direct influence on egg-laying date, while at high-altitude snow melt-out date was the limiting factor. At both elevations, air temperature had a similar effect on egg-laying date, but was a poorer predictor than larch budburst or snowmelt date. Our results shed light on proximate drivers of breeding phenology responses to interannual climate variability in mountain areas and suggest that factors directly influencing species phenology vary at different elevations. Predicting the future responses of species in a climate change context will require testing the transferability of models and accounting for nonstationary relationships between environmental predictors and the timing of phenological events.

Plant's-eye view of temperature governs elevational distributions

Explaining species geographic distributions by macroclimate variables is the most common approach for getting mechanistic insights into large-scale diversity patterns and range shifts. However, species' traits influencing biophysical processes can produce a large decoupling from ambient air temperature, which can seriously undermine biogeographical inference. We combined stable oxygen isotope theory with a trait-based approach to assess leaf temperature during carbon assimilation (T_L ) and its departure (ΔT) from daytime free air temperature during the growing season (T_gs ) for 158 plant species occurring from 3,400 to 6,150 m a.s.l. in Western Himalayas. We uncovered a general extent of temperature decoupling in the region. The interspecific variation in ΔT was best explained by the combination of plant height and δ¹³ C, and leaf dry matter content partly captured the variation in T_L . The combination of T_L and ΔT, with ΔT contributing most, explained the interspecific difference in elevational distributions. Stable oxygen isotope theory appears promising for investigating how plants perceive temperatures, a pivotal information to species biogeographic distributions.

Trait-based signatures of cloud base height in a tropical cloud forest

PREMISE

Clouds have profound consequences for ecosystem structure and function. Yet, the direct monitoring of clouds and their effects on biota is challenging especially in remote and topographically complex tropical cloud forests. We argue that known relationships between climate and the taxonomic and functional composition of plant communities may provide a fingerprint of cloud base height, thus providing a rapid and cost-effective assessment in remote tropical cloud forests.

METHODS

To detect cloud base height, we compared species turnover and functional trait values among herbaceous and woody plant communities in an ecosystem dominated by cloud formation. We measured soil and air temperature, soil nutrient concentrations, and extracellular enzyme activity. We hypothesized that woody and herbaceous plants would provide signatures of cloud base height, as evidenced by abrupt shifts in both taxonomic composition and plant function.

RESULTS

We demonstrated abrupt changes in taxonomic composition and the community- weighted mean of a key functional trait, specific leaf area, across elevation for both woody and herbaceous species, consistent with our predictions. However, abrupt taxonomic and functional changes occurred 100 m higher in elevation for herbaceous plants compared to woody ones. Soil temperature abruptly decreased where herbaceous taxonomic and functional turnover was high. Other environmental variables including soil biogeochemistry did not explain the abrupt change observed for woody plant communities.

CONCLUSIONS

We provide evidence that a trait-based approach can be used to estimate cloud base height. We outline how rises in cloud base height and differential environmental requirements between growth forms can be distinguished using this approach.

Effect of Feeding Adaptation of Italian Simmental Cows before Summer Grazing on Animal Behavior and Milk Characteristics

Simple Summary

The traditional transhumant system of rearing dairy cows in mountain areas expects animals to remain indoors in the valley during the cold season, whereas during the summer they are moved to pastures at progressively higher altitudes. The animals transferred from the valley farm to the alpine pasture must adapt to various management changes. This study aimed to evaluate whether a gradual inclusion of fresh grass in the diet of dairy cows in the valley farm can improve the performance and milk characteristics during summer grazing. Three groups of six animals each were considered: one group was kept in the stable, one was transferred from the valley to the summer farm without adaptation, and the other was progressively adapted to grazing with a feeding adaptation period. Compared to animals kept indoors, grazing animals had similar performance and milk characteristics, higher rumination time and, with respect to volatile compounds in milk, higher concentrations of alcohols, aldehydes, hydrocarbons, and ketones but lower concentrations of organic acids, phenolic compounds, and dimethyl sulfone, regardless of the feeding adaptation. In conclusion, the gradual inclusion of fresh grass in the diet in the valley farm did not improve the performance and milk characteristics during summer grazing.

Abstract

According to the alpine transhumance system, dairy cows are moved from indoor feeding with conserved forage to fresh herbage feeding on pasture. The aim of this study was to assess, as a feeding adaptation technique, the effect of a gradual inclusion of fresh herbage in the diet of Italian Simmental dairy cows before their transfer to alpine pasture on performance, behavior, and milk characteristics. Eighteen cows were assigned to three groups: animals transferred to alpine pasture with a 10-d feeding adaptation period consisting in gradual access to a pasture close to the valley farm (GT), animals transferred to alpine pasture without a feeding adaptation period (AT), and animals kept in the valley farm (IND). During the first two weeks of summer grazing, GT and AT showed higher rumination time and different concentrations of ketones, hydrocarbons, organic acids, toluene, alcohols, phenols, and dimethyl sulfone in milk as compared to IND, whereas no differences were found in milk yield, composition, or coagulation properties. No differences between GT and AT were evident for the studied variables. The feeding adaptation technique used in this study did not influence the performance and milk characteristics of Italian Simmental dairy cows grazing on alpine pasture.

Hypoxia is not the primary mechanism contributing to exercise-induced proteinuria

Introduction

Proteinuria increases at altitude and with exercise, potentially as a result of hypoxia. Using urinary alpha-1 acid glycoprotein (α1-AGP) levels as a sensitive marker of proteinuria, we examined the impact of relative hypoxia due to high altitude and blood pressure-lowering medication on post-exercise proteinuria.

Methods

Twenty individuals were pair-matched for sex, age and ACE genotype. They completed maximal exercise tests once at sea level and twice at altitude (5035 m). Losartan (100 mg/day; angiotensin-receptor blocker) and placebo were randomly assigned within each pair 21 days before ascent. The first altitude exercise test was completed within 24–48 hours of arrival (each pair within ~1 hour). Acetazolamide (125 mg two times per day) was administrated immediately after this test for 48 hours until the second altitude exercise test.

Results

With placebo, post-exercise α1-AGP levels were similar at sea level and altitude. Odds ratio (OR) for increased resting α1-AGP at altitude versus sea level was greater without losartan (2.16 times greater). At altitude, OR for reduced post-exercise α1-AGP (58% lower) was higher with losartan than placebo (2.25 times greater, p=0.059) despite similar pulse oximetry (SpO₂) (p=0.95) between groups. Acetazolamide reduced post-exercise proteinuria by approximately threefold (9.3±9.7 vs 3.6±6.0 μg/min; p=0.025) although changes were not correlated (r=−0.10) with significant improvements in SpO₂ (69.1%±4.5% vs 75.8%±3.8%; p=0.001).

Discussion

Profound systemic hypoxia imposed by altitude does not result in greater post-exercise proteinuria than sea level. Losartan and acetazolamide may attenuate post-exercise proteinuria, however further research is warranted.

Concentrations of Atmospheric Culturable Bioaerosols at Mountain and Seashore Sites

Concentrations of atmospheric culturable bioaerosols at mountain and seashore sites were measured in field investigations by using a bio-culture sampler. The eastern Korean peninsula was selected for the measurements because of the short distance between the mountain site and the seashore site. Detectable concentrations of culturable fungal and bacterial bioaerosols (maximum 1065 CFU/m3) were quantitatively measured at the mountain and seashore sites. In addition, measurement of bioaerosols was conducted at an urban area as reference data. Significantly higher concentrations of bioaerosols were found at the mountain site. However, several fold smaller levels of bioaerosols were detected at the seashore site (t-test p-value < 0.05).

BASE Jumping Fatalities Between 2007 and 2017: Main Causes of Fatal Events and Recommendations for Safety

INTRODUCTION

BASE (buildings, antennae, span, earth) jumping involves jumping from fixed objects with a parachute. This practice is associated with fatal events. Despite considerable evolution in BASE jump practice over the past years, fatalities have increased. Identifying the main causes of fatal events and recommending processes to reduce fatalities is vital for safe BASE jumping practice.

METHODS

In an effort to capture worldwide cases between 2007 and 2017, we identified and classified on a Haddon matrix each fatal event from the BASE jumping fatality list. Although not devoid of limitations, this is the most comprehensive list of BASE jumping fatal events and the main source of information on BASE-related fatalities for BASE jump participants.

RESULTS

The report noted 223 fatalities, 197 of them being cliff jumps. In addition, 137 fatal jumps were wingsuit jumps. Impact and object strike were the main cause of fatal event (96%). Human factors leading to fatality were mostly low pull/no pull (64%) and bad exits (15%). Equipment factors included off-heading openings, twists, and pilot chute entanglement. Environmental factors included strong wind, poor visibility, and water.

CONCLUSIONS

BASE jump practice has undergone radical transformations in the last 10 y, especially linked to the mountain environment and the use of wingsuits. These factors were linked to most fatal events. Key recommendations are basic practical measures, such as ground preparation and equipment checks, and deep technical and personal knowledge that involves regular engagement and significant introspection.

Warm temperatures during cold season can negatively affect adult survival in an alpine bird

Climate seasonality is a predominant constraint on the lifecycles of species in alpine and polar biomes. Assessing the response of these species to climate change thus requires taking into account seasonal constraints on populations. However, interactions between seasonality, weather fluctuations, and population parameters remain poorly explored as they require long-term studies with high sampling frequency. This study investigated the influence of environmental covariates on the demography of a corvid species, the alpine chough Pyrrhocorax graculus, in the highly seasonal environment of the Mont Blanc region. In two steps, we estimated: (1) the seasonal survival of categories of individuals based on their age, sex, etc., (2) the effect of environmental covariates on seasonal survival. We hypothesized that the cold season-and more specifically, the end of the cold season (spring)-would be a critical period for individuals, and we expected that weather and individual covariates would influence survival variation during critical periods. We found that while spring was a critical season for adult female survival, it was not for males. This is likely because females are dominated by males at feeding sites during snowy seasons (winter and spring), and additionally must invest energy in egg production. When conditions were not favorable, which seemed to happen when the cold season was warmer than usual, females probably reached their physiological limits. Surprisingly, adult survival was higher at the beginning of the cold season than in summer, which may result from adaptation to harsh weather in alpine and polar vertebrates. This hypothesis could be confirmed by testing it with larger sets of populations. This first seasonal analysis of individual survival over the full life cycle in a sedentary alpine bird shows that including seasonality in demographic investigations is crucial to better understand the potential impacts of climate change on cold ecosystems.

The role of ant nests in European ground squirrel's (Spermophilus citellus) post-reintroduction adaptation in two Bulgarian mountains

The European ground squirrel (Spermophiluscitellus) is a vulnerable species, whose populations are declining throughout its entire range in Central and South-Eastern Europe. To a great extent, its conservation depends on habitat restoration, maintenance and protection. In order to improve the conservation status of the species, reintroductions are increasingly applied. Therefore, researchers focus their attention on factors that facilitate these activities and contribute to their success. In addition to the well-known factors like grass height and exposition, others, related to the underground characteristics, are more difficult to evaluate. The presence of other digging species could help this evaluation. Here, we present two reintroduced ground squirrel colonies, where the vast majority of the burrows are located in the base of anthills, mainly of yellow meadow ant (Lasiusflavus). This interspecies relationship offers numerous advantages for the ground squirrel and is mostly neutral for the ants. The benefits for the ground squirrel, including reduced energy demand for digging, as well as additional surveillance and hiding places available, could greatly enhance the post-reintroduction adaptation process.

Disentangling how climate change can affect an aquatic food web by combining multiple experimental approaches

Predicting the biological effects of climate change presents major challenges due to the interplay of potential biotic and abiotic mechanisms. Climate change can create unexpected outcomes by altering species interactions, and uncertainty over the ability of species to develop in situ tolerance or track environmental change further hampers meaningful predictions. As multiple climatic variables shift in concert, their potential interactions further complicate ecosystem responses. Despite awareness of these complexities, we still lack controlled experiments that manipulate multiple climatic stressors, species interactions, and prior exposure of species to future climatic conditions. Particularly studies that address how changes in water availability interact with other climatic stressors to affect aquatic ecosystems are still rare. Using aquatic insect communities of Neotropical tank bromeliads, we combined controlled manipulations of drought length and species interactions with a space-for-time transplant (lower elevations represent future climate) and a common garden approach. Manipulating drought length and experiment elevation revealed that adverse effects of drought were amplified at the warmer location, highlighting the potential of climatic stressors to synergistically affect communities. Manipulating the presence of omnivorous tipulid larvae showed that negative interactions from tipulids, presumably from predation, arose under drought, and were stronger at the warmer location, stressing the importance of species interactions in mediating community responses to climate change. The common garden treatments revealed that prior community exposure to potential future climatic conditions did not affect the outcome. In this powerful experiment, we demonstrated how complexities arise from the interplay of biotic and abiotic mechanisms of climate change. We stress that single species can steer ecological outcomes, and suggest that focusing on such disproportionately influential species may improve attempts at making meaningful predictions of climate change impacts on food webs.

Factors determining species richness patterns of breeding birds along an elevational gradient in the Horn of Africa region

AIM

To document the species richness patterns of breeding birds along elevational gradients and explore its drivers in the Horn of Africa region.

LOCATION

Horn of Africa region.

TAXON

Breeding birds.

METHODS

Distributional data for breeding birds were collected. Elevational distribution data were extracted, interpolated, and assembled for all birds, passerines, and nonpasserines. In order to tease apart how different environmental factors contributed to the variation in species richness, we found it is necessary to divide the area into four subregions with different climatic regimes and topographic structure, namely western slope, eastern slope, wet side, and dry side. Then, the species richness in each 100-m elevational band was counted along the elevational gradients of each subregion. Pearson's correlation analyses and ordinary least squares (OLS) regressions were used to examine the relationships between species richness and factors.

RESULTS

The variation in species richness followed hump-shaped patterns for all subregions, although with peak values at different elevations. The bird species groups on the western and eastern slopes showed low and high plateaus with mid-elevation peaks, respectively, but very low species diversities at the highest elevations. Species richness was significantly correlated with temperature range and productivity in each subregion. The temperature range, area, and productivity explained 82% of the species richness variations for all birds on the western slope.

MAIN CONCLUSIONS

The separate analyses of four area subdivisions provide strong indications of how various factors interact. Productivity and temperature range were the major driving factors for shaping the richness patterns, but deviations from expected patterns suggest modifying roles of mist formation zones in the valleys that deeply intersect the large highlands in the west and rich riparian vegetation where water from cool and humid environments at high elevation reaches lower elevations in the arid east. Conservation is recommended in each subregion based on the elevational richness scenarios.

Accelerating forest loss in Southeast Asian Massif in the 21st century: A case study in Nan Province, Thailand

Farmers are carving a new agricultural frontier from the forests in the Southeast Asian Massif (SAM) in the 21st century, triggering significant environment degradation at the local scale; however, this frontier has been missed by existing global land use and forest loss analyses. In this paper, we chose Thailand's Nan Province, which is located in the geometric center of SAM, as a case study, and combined high resolution forest cover change product with a fine-scale land cover map to investigate land use dynamics with respect to topography in this region. Our results show that total forest loss in Nan Province during 2001-2016 was 66,072 ha (9.1% of the forest cover in 2000), and that the majority of this lost forest (92%) had been converted into crop (mainly corn) fields by 2017. Annual forest loss is significantly correlated with global corn price (p < 0.01), re-confirming agricultural expansion as a key driver of forest loss in Nan Province. Along with the increasing global corn price, forest loss in Nan Province has accelerated at a rate of 2,616 ± 730 ha per decade (p < 0.01). Global corn price peaked in 2012, in which year annual forest loss also reached its peak (7,523 ha); since then, the location of forest loss has moved to steeper land at higher elevations. Spatially, forest loss driven by this smallholder agricultural expansion emerges as many small patches that are not recognizable even at a moderate spatial resolution (e.g. 300 m). It explains how existing global land use/cover change products have missed the widespread and rapid forest loss in SAM. It also highlights the importance of high-resolution observations to evaluate the environmental impacts of agricultural expansion and forest loss in SAM, including, but not limited to, the impacts on the global carbon cycle, regional hydrology, and local environmental degradation.

Storm impacts on alpine lakes: Antecedent weather conditions matter more than the event intensity

Extreme weather events may be just as important as gradual trends for the long-term trajectories of ecosystems. For alpine lakes, which are exposed to both exacerbated atmospheric warming and intense episodic weather events, future conditions might not be appropriately forecast by only climate change trends, i.e. warming, if extreme events have the potential to deflect their thermal and metabolic states from their seasonal ranges. We used high-frequency monitoring data over three open-water seasons with a one-dimensional hydrodynamic model of the high-altitude Lake Muzelle (France) to show that rainstorms or windstorms, notwithstanding their intensity, did not trigger long-lasting consequences to the lake characteristics when light penetration into the lake was not modified. In contrast, storms associated with high turbidity input from the watershed ("turbid storms") strongly modified the lacustrine hydrodynamics and metabolism for the rest of the open-water season through reduced light penetration. The long-lasting effects of turbid storms were related to the inputs and in-lake persistence of very light glacial suspensoids from the watershed. The occurrence of the observed turbid storms was not related to the wind or rain intensities during the events. Instead, the turbid storms occurred after dry and atypically warm spells, i.e. meteorological conditions expected to be more frequent in this alpine region in the upcoming decades. Consequently, storm events, notwithstanding their intensity, are expected to strongly imprint the future ecological status of alpine lakes under climate warming.

Range dynamics of mountain plants decrease with elevation

Many studies report that mountain plant species are shifting upward in elevation. However, the majority of these reports focus on shifts of upper limits. Here, we expand the focus and simultaneously analyze changes of both range limits, optima, and abundances of 183 mountain plant species. We therefore resurveyed 1,576 vegetation plots first recorded before 1970 in the European Alps. We found that both range limits and optima shifted upward in elevation, but the most pronounced trend was a mean increase in species abundance. Despite huge species-specific variation, range dynamics showed a consistent trend along the elevational gradient: Both range limits and optima shifted upslope faster the lower they were situated historically, and species' abundance increased more for species from lower elevations. Traits affecting the species' dispersal and persistence capacity were not related to their range dynamics. Using indicator values to stratify species by their thermal and nutrient demands revealed that elevational ranges of thermophilic species tended to expand, while those of cold-adapted species tended to contract. Abundance increases were strongest for nutriphilous species. These results suggest that recent climate warming interacted with airborne nitrogen deposition in driving the observed dynamics. So far, the majority of species appear as "winners" of recent changes, yet "losers" are overrepresented among high-elevation, cold-adapted species with low nutrient demands. In the decades to come, high-alpine species may hence face the double pressure of climatic changes and novel, superior competitors that move up faster than they themselves can escape to even higher elevations.

Legacy Effects of Climate Extremes in Alpine Grassland

Climate change is particularly apparent in many mountainous regions, with warming rates of more than twice the global average being reported for the European Alps. As a result, the probability of climate extremes has increased and is expected to rise further. In an earlier study, we looked into immediate impacts of experimentally imposed heat waves in alpine grassland, and found that these systems were able to cope with heat as long as enough water was available. However, concomitant drought led to increased stress, and reduced aboveground biomass production and green plant cover. Here, we studied the legacy effects (lag-effects) of the imposed climate extreme to see whether delayed responses occurred and how fast the alpine grassland could rebound from the initial changes. Green cover continued to be suppressed the two following years in communities that had been exposed to the most intense hot drought, while aboveground biomass production had returned to control levels by year 2. The initial lower resistance of the forb fraction in the communities was not compensated by faster recovery later on. This resulted in alpine communities that became (and remained) relatively enriched with graminoids, which resisted the original extreme better. The responses of alpine grassland to heat extremes with or without drought observed in this study resemble those typically found in lowland grassland in the short term. However, alpine grassland exhibited longer legacy effects from an annual perspective, with delayed recovery of aboveground production and persistent changes in community composition. This suggests that once initial resistance thresholds are exceeded, impacts may be longer-lasting in alpine grassland, where recovery is constrained by both the short growing season and difficult seedling establishment.

Fall-related accidents among hikers in the Austrian Alps: a 9-year retrospective study

Objective

To analyse the circumstances of fatal and non-fatal mountain hiking accidents caused by falls.

Methods

The study was designed as a retrospective analysis. Mountain hiking accidents caused by falls were documented during a 9-year period (2006–2014). After screening of all data for potential exclusion criteria the final sample size of 5368 accidents and 5665 victims was included into the analyses. Main outcome measures were details about accidents, victims, type of trail and surface.

Results

The annual number of accidents showed a continuous increase from 467 in 2006 to 700 in 2014. In total, 5.8% of all victims died during the 9-year period. 75.3% of the hikers fell during descent and 80.9% of the victims had their accident on a marked hiking trail or small path. The sex ratio for non-fatal accidents was 55% female and 45% male; for fatal accidents the female-to-male ratio was 28%:72%. Mean age of all victims was 52.5±17.5 years and victims of fatalities were about 5 years older compared with victims of non-fatal accidents (57.5±16.5 vs 52.2±17.5 years, P<0.01).

Conclusion

Descent is the most risky part for accidents caused by falls during mountain hiking. Male hikers are at greater risk for fatalities independent of age and this is associated with accidents occurring in pathless terrain. The death rate from falls was 6%. We recommend a critical self-assessment of the individual capabilities and mountain hiking skills and adequate planning of the hiking tours for mountain hikers.

Multidate, multisensor remote sensing reveals high density of carbon-rich mountain peatlands in the páramo of Ecuador

Tropical peatlands store a significant portion of the global soil carbon (C) pool. However, tropical mountain peatlands contain extensive peat soils that have yet to be mapped or included in global C estimates. This lack of data hinders our ability to inform policy and apply sustainable management practices to these peatlands that are experiencing unprecedented high rates of land use and land cover change. Rapid large-scale mapping activities are urgently needed to quantify tropical wetland extent and rate of degradation. We tested a combination of multidate, multisensor radar and optical imagery (Landsat TM/PALSAR/RADARSAT-1/TPI image stack) for detecting peatlands in a 2715 km² area in the high elevation mountains of the Ecuadorian páramo. The map was combined with an extensive soil coring data set to produce the first estimate of regional peatland soil C storage in the páramo. Our map displayed a high coverage of peatlands (614 km² ) containing an estimated 128.2 ± 9.1 Tg of peatland belowground soil C within the mapping area. Scaling-up to the country level, páramo peatlands likely represent less than 1% of the total land area of Ecuador but could contain as much as ~23% of the above- and belowground vegetation C stocks in Ecuadorian forests. These mapping approaches provide an essential methodological improvement applicable to mountain peatlands across the globe, facilitating mapping efforts in support of effective policy and sustainable management, including national and global C accounting and C management efforts.

Integrative overview of the herpetofauna from Serra da Mocidade, a granitic mountain range in northern Brazil

The Brazilian mountain ranges from the Guiana Shield highlands are largely unexplored, with an understudied herpetofauna. Here the amphibian and reptile species diversity of the remote Serra da Mocidade mountain range, located in extreme northern Brazil, is reported upon, and biogeographical affinities and taxonomic highlights are discussed. A 22-days expedition to this mountain range was undertaken during which specimens were sampled at four distinct altitudinal levels (600, 960, 1,060 and 1,365 m above sea level) using six complementary methods. Specimens were identified through an integrated approach that considered morphological, bioacoustical, and molecular analyses. Fifty-one species (23 amphibians and 28 reptiles) were found, a comparable richness to other mountain ranges in the region. The recorded assemblage showed a mixed compositional influence from assemblages typical of other mountain ranges and lowland forest habitats in the region. Most of the taxa occupying the Serra da Mocidade mountain range are typical of the Guiana Shield or widely distributed in the Amazon. Extensions of known distribution ranges and candidate undescribed taxa are also recorded. This is the first herpetofaunal expedition that accessed the higher altitudinal levels of this mountain range, contributing to the basic knowledge of these groups in remote areas.

Managing diabetes at high altitude: personal experience with support from a Multidisciplinary Physical Activity and Diabetes Clinic

OBJECTIVE

Physical activity is important for well-being but can be challenging for people with diabetes. Data informing support of specialist activities such as climbing and high-altitude trekking are limited. A 42-year-old man with type 1 diabetes (duration 30 years) attended a Multidisciplinary Physical Activity and Diabetes Clinic planning to climb Mont Blanc during the summer and trek to Everest Base Camp in the autumn. His aims were to complete these adventures without his diabetes impacting on their success.

METHODS

We report the information provided that enabled him to safely facilitate his objectives, in particular, the requirement for frequent checking of blood glucose levels, the effects of altitude on insulin dose requirements, and recognition that acute mountain sickness may mimic the symptoms of hypoglycaemia and vice versa. Real-time continuous glucose monitoring was made available for his treks.

RESULTS

The effects of high altitude on blood glucose results and glycaemic variability while treated on multiple daily injections of insulin are reported. In addition, we present a first-person account of his experience and lessons learnt from managing diabetes at high altitude.

CONCLUSIONS

A dedicated Multidisciplinary Physical Activity and Diabetes Clinic delivering individualised, evidence-based, patient-focused advice on the effects of altitude on blood glucose levels, and provision of real-time continuous glucose monitoring enabled uneventful completion of a trek to Everest Base Camp in a person with type 1 diabetes.

Relationships between Personal and Collective Place Identity and Well-Being in Mountain Communities

The aim was to investigate the relationships between landscape-related personal and collective identity and well-being of residents living in a Swedish mountain county (N = 850). It was shown that their most valued mountain activities were viewing and experiencing nature and landscape, outdoor recreation, rest and leisure, and socializing with friends/family. Qualitative analyses showed that the most valued aspects of the sites were landscape and outdoor restoration for personal favorite sites, and tourism and alpine for collective favorite sites. According to quantitative analyses the stronger the attachment/closeness/belonging (emotional component of place identity) residents felt to favorite personal and collective sites the more well-being they perceived when visiting these places. Similarly, the more remembrance, thinking and mental travel (cognitive component of place identity) residents directed to these sites the more well-being they perceived in these places. In both types of sites well-being was more strongly predicted by emotional than cognitive component of place-identity. All this indicates the importance of person-place bonds in beneficial experiences of the outdoors, over and above simply being in outdoor environments.

Climate change and alpine stream biology: progress, challenges, and opportunities for the future

In alpine regions worldwide, climate change is dramatically altering ecosystems and affecting biodiversity in many ways. For streams, receding alpine glaciers and snowfields, paired with altered precipitation regimes, are driving shifts in hydrology, species distributions, basal resources, and threatening the very existence of some habitats and biota. Alpine streams harbour substantial species and genetic diversity due to significant habitat insularity and environmental heterogeneity. Climate change is expected to affect alpine stream biodiversity across many levels of biological resolution from micro- to macroscopic organisms and genes to communities. Herein, we describe the current state of alpine stream biology from an organism-focused perspective. We begin by reviewing seven standard and emerging approaches that combine to form the current state of the discipline. We follow with a call for increased synthesis across existing approaches to improve understanding of how these imperiled ecosystems are responding to rapid environmental change. We then take a forward-looking viewpoint on how alpine stream biologists can make better use of existing data sets through temporal comparisons, integrate remote sensing and geographic information system (GIS) technologies, and apply genomic tools to refine knowledge of underlying evolutionary processes. We conclude with comments about the future of biodiversity conservation in alpine streams to confront the daunting challenge of mitigating the effects of rapid environmental change in these sentinel ecosystems.

Simulated heat waves affected alpine grassland only in combination with drought

The Alpine region is warming fast, and concurrently, the frequency and intensity of climate extremes are increasing. It is currently unclear whether alpine ecosystems are sensitive or resistant to such extremes. We subjected Swiss alpine grassland communities to heat waves with varying intensity by transplanting monoliths to four different elevations (2440-660 m above sea level) for 17 d. Half of these were regularly irrigated while the other half were deprived of irrigation to additionally induce a drought at each site. Heat waves had no significant impacts on fluorescence (Fv /Fm , a stress indicator), senescence and aboveground productivity if irrigation was provided. However, when heat waves coincided with drought, the plants showed clear signs of stress, resulting in vegetation browning and reduced phytomass production. This likely resulted from direct drought effects, but also, as measurements of stomatal conductance and canopy temperatures suggest, from increased high-temperature stress as water scarcity decreased heat mitigation through transpiration. The immediate responses to heat waves (with or without droughts) recorded in these alpine grasslands were similar to those observed in the more extensively studied grasslands from temperate climates. Responses following climate extremes may differ in alpine environments, however, because the short growing season likely constrains recovery.

Special Issue: Mycorrhizal Fungi in Sensitive Environments

The scope of this special issue is to understand whether and how mycorrhizal symbiosis can be included as an agriculture and agroforestry tool that promotes more environmentally friendly practices, and whether it promotes the protection of sensitive areas. Three papers are included in this special issue, each dealing with a different sensitive environment. These papers present fundamental aspects that should be taken into account when planning or reporting studies related to mycorrhizal fungi in sensitive environments.

As old as the mountains: the radiations of the Ericaceae

Mountains are often more species-rich than lowlands. This could be the result of migration from lowlands to mountains, of a greater survival rate in mountains, or of a higher diversification rate in mountains. We investigated this question in the globally distributed family Ericaceae, which includes c. 4426 species ranging from sea level to > 5000 m. We predict that the interaction of low specific leaf area (SLA) and montane habitats is correlated with increased diversification rates. A molecular phylogeny of Ericaceae based on rbcL and matK sequence data was built and dated with 18 fossil calibrations and divergence time estimates. We identified radiations using bamm and correlates of diversification rate changes using binary-state speciation and extinction (BiSSE) and multiple-state speciation and extinction (MuSSE) analyses. Analyses revealed six largely montane radiations. Lineages in mountains diversified faster than nonmountain lineages (higher speciation rate, but no difference in extinction rate), and lineages with low SLA diversified faster than high-SLA lineages. Further, habitat and trait had a positive interactive effect on diversification. Our results suggest that the species richness in mountains is the result of increased speciation rather than reduced extinction or increased immigration. Increased speciation in Ericaceae was facilitated by low SLA.