High-altitude Mountain Areas Research Articles

Spatiotemporal variations of forest phenology in the Qinling Mountains and its response to a critical temperature of 10°C

Based on the fifth version MOD09A1 product of NASA LP DAAC (Land Processes Distributed Active Center) from 2001 to 2016, an enhanced vegetation index (EVI) time series dataset in the Qinling Mountains was reconstructed; it was used to extract the plant phenological parameters of the region by employing the maximal slopes of the alteration method and threshold method. The results show that the Whittaker filter method was better than other methods for the reconstruction of shrubland, farmland, and forest in the Qinling Mountains. Based on the reconstructed EVI, the characteristics of vegetation coverage, the start of growth season (SOG), the end of growth season (EOG), and the length of growth season (LOG) in the Qinling Mountains were all analyzed. There was an increasing trend of vegetation coverage in most regions (about 89.93% of the monitored areas) over the Qinling Mountains in the past decades, and the average phenological distribution pattern in the Qinling Mountains was closely related to the local hydrothermal conditions. From the high altitude mountainous areas to the farming areas, the SOG was gradually postponed, the EOG was gradually earlier, and the LOG gradually shortened. Furthermore, the time series variation of SOG, EOG, and LOG from 2001 to 2016 in the Qinling Mountains was also studied. The variation showed that the SOG shifted earlier, which was more prominent in high-altitude areas, while, for some southern and northern foothills altitude below 500 m and a few areas of the eastern Funiu Mountains, the SOG was delayed. The EOG shifted later, which was more apparent in the northern Qinling foothills and mid- to low-altitude areas of the eastern ranges, and the LOG was extended. Finally, the studies of correlation analysis between the plant phenology and a temperature threshold of 10°C showed that global warming was the major factor affecting the phytophenology of the Qinling Mountains, and the effects were concentrated mainly in the 1000- to 2000-m zones of the southern and northern Qinling Mountains. Moreover, the northern Qinling foothills showed a greater response to accumulated temperature than the southern foothills, and the low-altitude area of the eastern Funiu Mountains exhibited the lowest correlation with the accumulated temperature.

Effects of Mountain Uplift and Climatic Oscillations on Phylogeography and Species Divergence in Four Endangered Notopterygium Herbs.

Mountain uplift and climatic fluctuations are important driving forces that have affected the geographic distribution and population dynamics history of organisms. However, it is unclear how geological and climatic events might have affected the phylogeographic history and species divergence in high-alpine herbal plants. In this study, we analyzed the population demographic history and species differentiation of four endangered Notopterygium herbs on the high-altitude Qinghai–Tibetan Plateau (QTP) and adjacent areas. We combined phylogeographic analysis with species distribution modeling to detect the genetic variations in four Notopterygium species (N. incisum, N. franchetii, N. oviforme, and N. forrestii). In total, 559 individuals from 74 populations of the four species were analyzed based on three maternally inherited chloroplast fragments (matK, rbcL, and trnS-trnG) and one nuclear DNA region (internal transcribed spacer, ITS). Fifty-five chloroplast DNA (cpDNA) and 48 ITS haplotypes were identified in the four species. All of the cpDNA and ITS haplotypes were species-specific, except N. franchetii and N. oviforme shared one cpDNA haplotype, H32. Phylogenetic analysis suggested that all four species formed a monophyletic clade with high bootstrap support, where N. franchetii and N. oviforme were sisters. In addition, each Notopterygium species generated an individual clade that corresponded to their respective species in the ITS tree. Population dynamics analyses and species distribution modeling showed that the two widely distributed herbs N. incisum and N. franchetii exhibited obvious demographic expansions during the Pleistocene ice ages. Molecular dating suggested that the divergence of the four Notopterygium species occurred approximately between 3.6 and 1.2 Mya, and it was significantly associated with recent extensive uplifts of the QTP. Our results support the hypothesis that mountain uplift and Quaternary climatic oscillations profoundly shaped the population genetic divergence and demographic dynamics of Notopterygium species. The findings of this and previous studies provide important insights into the effects of QTP uplifts and climatic changes on phylogeography and species differentiation in high altitude mountainous areas. Our results may also facilitate the conservation of endangered herbaceous medicinal plants in the genus Notopterygium.

Interventions for preventing high altitude illness: Part 1. Commonly-used classes of drugs.

High altitude illness (HAI) is a term used to describe a group of cerebral and pulmonary syndromes that can occur during travel to elevations above 2500 metres (8202 feet). Acute hypoxia, acute mountain sickness (AMS), high altitude cerebral oedema (HACE) and high altitude pulmonary oedema (HAPE) are reported as potential medical problems associated with high altitude. In this review, the first in a series of three about preventive strategies for HAI, we assess the effectiveness of six of the most recommended classes of pharmacological interventions. To assess the clinical effectiveness and adverse events of commonly-used pharmacological interventions for preventing acute HAI. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (OVID), Embase (OVID), LILACS and trial registries in January 2017. We adapted the MEDLINE strategy for searching the other databases. We used a combination of thesaurus-based and free-text terms to search. We included randomized-controlled and cross-over trials conducted in any setting where commonly-used classes of drugs were used to prevent acute HAI. We used standard methodological procedures as expected by Cochrane. We included 64 studies (78 references) and 4547 participants in this review, and classified 12 additional studies as ongoing. A further 12 studies await classification, as we were unable to obtain the full texts. Most of the studies were conducted in high altitude mountain areas, while the rest used low pressure (hypobaric) chambers to simulate altitude exposure. Twenty-four trials provided the intervention between three and five days prior to the ascent, and 23 trials, between one and two days beforehand. Most of the included studies reached a final altitude of between 4001 and 5000 metres above sea level. Risks of bias were unclear for several domains, and a considerable number of studies did not report adverse events of the evaluated interventions. We found 26 comparisons, 15 of them comparing commonly-used drugs versus placebo. We report results for the three most important comparisons: Acetazolamide versus placebo (28 parallel studies; 2345 participants)The risk of AMS was reduced with acetazolamide (risk ratio (RR) 0.47, 95% confidence interval (CI) 0.39 to 0.56; I2 = 0%; 16 studies; 2301 participants; moderate quality of evidence). No events of HAPE were reported and only one event of HACE (RR 0.32, 95% CI 0.01 to 7.48; 6 parallel studies; 1126 participants; moderate quality of evidence). Few studies reported side effects for this comparison, and they showed an increase in the risk of paraesthesia with the intake of acetazolamide (RR 5.53, 95% CI 2.81 to 10.88, I2 = 60%; 5 studies, 789 participants; low quality of evidence). Budenoside versus placebo (2 parallel studies; 132 participants)Data on budenoside showed a reduction in the incidence of AMS compared with placebo (RR 0.37, 95% CI 0.23 to 0.61; I2 = 0%; 2 studies, 132 participants; low quality of evidence). Studies included did not report events of HAPE or HACE, and they did not find side effects (low quality of evidence). Dexamethasone versus placebo (7 parallel studies; 205 participants)For dexamethasone, the data did not show benefits at any dosage (RR 0.60, 95% CI 0.36 to 1.00; I2 = 39%; 4 trials, 176 participants; low quality of evidence). Included studies did not report events of HAPE or HACE, and we rated the evidence about adverse events as of very low quality. Our assessment of the most commonly-used pharmacological interventions suggests that acetazolamide is an effective pharmacological agent to prevent acute HAI in dosages of 250 to 750 mg/day. This information is based on evidence of moderate quality. Acetazolamide is associated with an increased risk of paraesthesia, although there are few reports about other adverse events from the available evidence. The clinical benefits and harms of other pharmacological interventions such as ibuprofen, budenoside and dexamethasone are unclear. Large multicentre studies are needed for most of the pharmacological agents evaluated in this review, to evaluate their effectiveness and safety.

Effects of atmospheric circulation on summertime precipitation variability and glacier mass balance over the Tuyuksu Glacier in Tianshan Mountains, Kazakhstan

The amount and the form of precipitation have significant effects on glacier mass balances in high altitude mountain areas by controlling the accumulation, the ablation and the energy balance of a glacier through impact on the surface albedo. The liquid precipitation has negative effects on glacier accumulation and may increase the ablation of surface ice through the heat input for melting. The timing and the forms of precipitation over glacierized regions depend on the weather processes both locally and regionally. Early studies showed that regional to large-scale atmospheric circulation processes play a key role in affecting the precipitation events over glaciers. This paper analyzed the relationship between the inter-annual variability of the summertime precipitation over the Tuyuksu Glacier and the atmospheric circulation types, which related to various atmospheric circulation types in the Northern Hemisphere. Results indicated that the decrease in the duration of zonal processes and the increase in the meridional northern processes were observed in the last decade. The total summer precipitation associated with these processes also increased along with an increase of summertime solid precipitation. Although the decadal fluctuation of glaciological parameters were found in dependent of the above large-scale atmospheric circulation processes, global warming was a dominant factor leading to the mass loss in the recent decades under the background of the increase in precipitation over the Tuyuksu Glacier.

A Revision of Selected Clades of Neotropical Mite Harvestmen (Arachnida, Opiliones, Cyphophthalmi, Neogoveidae) with the Description of Eight New Species

Among the least-studied families of mite harvestmen (Opiliones, Cyphophthalmi) is the family Neogoveidae, a group of arachnids that inhabits tropical rain forests on both sides of the Atlantic Ocean around the Equator, and an exquisite example of Gondwanan vicariance. To evaluate the diversity within Neogoveidae we studied the morphology of all currently recognized genera using a recent phylogeny of the group to provide a framework for the family in the Neotropics. That study identifies several clades that correspond to the recognized genera Neogovea, Huitaca, Metagovea, Canga, and the recently resurrected genus Brasilogovea, formerly synonymized with Neogovea. Neogovea is restricted to eastern Amazonia (Brazil, Guyana, French Guiana, Suriname), Huitaca remains endemic to Colombia, Canga is restricted to its type locality in the Serra de Carajás (Pará State, Brazil), Brasilogovea to Central Amazonas and the Tepuis region in Colombia, and Metagovea is the most widespread genus, found along the northern Andes from Perú to Venezuela, and extending to the Amazon region. All Neotropical genera are diagnosed and discussed. The formerly monotypic Huitaca is revised with the description of six additional species, all found in the high-altitude Colombian mountain areas called cordilleras, between 2,030 and 3,050 m. These include: Huitaca bitaco new species, Huitaca boyacaensis new species, Huitaca caldas new species, Huitaca depressa new species, Huitaca sharkeyi new species, and Huitaca tama new species, all from Colombia. Two additional species, Brasilogovea chiribiqueta new species, from Colombia, and Neogovea hormigai new species, from Guyana, are also described.

Taxonomy and distribution of Grimmia (Bryophyta) in mountain regions of the Northeastern United States

Summarized are results of field studies of small, cushion-forming species of Grimmia in high altitude mountain areas of New York State, Vermont, New Hampshire, and Maine, and of associated research with herbarium specimens from these regions. We here report eight species. Grimmia anodon is added to the flora of the Northeast, and new records and clarifications are presented for G. donniana, G. incurva, G. longirostris, G. milleri, G. sessitana, and G. trichophylla. Collections of these species came from rock types of varying composition (calcareous to acidic), sometimes different vegetation, and varying altitudinal ranges. In spite of these advancements in knowledge, Grimmia of the northeastern United States remains incompletely understood, taxonomically and ecologically.

中部山岳地域における気象観測の現状とその意義

The Japanese Alps collectively refer the Hida Mountains, Kiso Mountains, and Akaishi Mountains, ranging approximately 200 km north to south and 100 km east to west. In terms of span, the Japanese Alps region includes the Ryohaku Mountains to the west and Mt. Fuji, Mt. Yatsugatake, and Mikuni Mountains to the east, making the geographical extent of the region more than 200 km in the east-west direction. The maximum altitude of the Japanese Alps is around 3000 m; however, climatic conditions vary widely because the region lies at the center of Honshu, between the Japan Sea coast and the Pacific coast, and the northern area is known to experience one of the heaviest snowfalls in the world. It is thought that mountainous areas are particularly sensitive to global-scale environmental changes, such as warming. When attempting to evaluate the effect of a global-scale warming event on regional environmental change in the high-altitude Japanese Alps, we note a lack of high-altitude meteorological observation data. This presents difficulties when evaluating the effects of warming on ecological systems and water resources in mountainous regions. In this study, we discuss long-term variations of winter temperature, as well as the amount of snowfall and depth of snow cover at twelve observational stations in the Japan Alps region. At eleven sites other than Mt. Fuji, a trend of increasing annual minimum temperature is recognized, which is statistically significant at the 1% significance level. At locations such as Mt. Fuji, which are located at extremely high altitudes, the annual minimum temperature over the last several decades has not been seen to increase or decrease. The trend of decreasing annual cumulative snowfall is statistically significant at the 10% level at Takada, Toyama and Kanazawa stations. At the other eight sites, it is shown that the recent annual cumulative snowfall does not show either an increasing or decreasing trend. The increasing trend of the annual maximum snow depth is statistically significant at the 5% level at Mt. Fuji, whereas a decreasing trend of the annual maximum snow depth is statistically significant at the 10% level at Takada and Kanazawa. At the other nine sites, annual maximum snow depth has not shown a statistically significant change in recent decades. Recent studies report that the amount of snowfall in Japan will decrease as a result of global warming; however, these studies use data collected at low altitudes. It is, therefore, important to question whether the same theory can be applied to high-altitude mountainous areas. In high-altitude areas of the Japanese Alps region, it is reasonable to expect that a cold atmosphere will be maintained even with global warming, and an increase in evaporated moisture vapor in the air caused by warming on a global scale will increase the amount of snowfall in the region.

Cold Acclimation Proteome Analysis Reveals Close Link between the Up-Regulation of Low-Temperature Associated Proteins and Vernalization Fulfillment

Low-temperature (LT) stress is one of the major limiting factors in cereal production in cold high-altitude mountainous areas of Iran where cereals are exposed to variable periods of temperatures in the vernalization range during the autumn season. Cereals regulate their development through adaptive mechanisms that are responsive to low but nonfreezing temperatures. We exploited a proteomic approach to determine the interrelationship between vernalization fulfillment and expression of low-temperature (LT)-induced protein in most hardy Norstar and semi-hardy Azar2 wheat (Triticum aestivum L. em. Thell). These cultivars were subjected to 12 h of cold acclimating temperature (2 °C) over a period of 0-89 days. LT tolerance, as measured by LT50, and vernalization fulfillment, as estimated from final leaf number (FLN), was determined at intervals throughout the acclimation period. A significant decrease in FLN associated with LT treatment indicated that Norstar and Azar2 had vernalization responses. Azar2 achieved its vernalization fulfillment and maximum LT tolerance (∼ -8 °C) by 28 days of acclimation. However, Norstar had a longer vernalization requirement (between 35 and 42 days) and reached vernalization fulfillment and maximum LT tolerance (∼ -18.7 °C) about the same time as vernalization fulfillment. We applied a two-dimensional electrophoresis-based proteomics approach to analyze changes in the leaf proteome of two genotypes, Norstar and Azar2, during cold acclimation. Using MALDI-TOF/TOF mass spectrometry, 66 LT-associated proteins could significantly be identified. These proteins were categorized into cold-regulated proteins, antifreezing proteins, oxidative stress defense, photosynthesis, chloroplast post-transcriptional regulation, metabolisms, and protein synthesis. A close association between the vernalization fulfillment and the start of a decline in the protein accumulation of hardy Norstar with a long vernalization requirement and semi-hardy Azar2 with a short vernalization requirement was observed. This finding supported the hypothesis that developmental trait which was regulated by vernalization had a regulatory influence over LT proteome response and highlight a close link between the up-regulation of LT-associated proteins and vernalization fulfillment at the molecular level in wheat.

Indigenous Yak and Yak‐Cattle Crossbreed Management in High Altitude Areas of Northern Nepal: A Case Study from Rasuwa District

This paper summarizes and documents the indigenous yak and chauri managements in high altitude mountainous areas of Nepal through on-the-spot surveys on the farmers from three villages of case study site, Rasuwa district, 35 households were surveyed with open-ended and pre-tested questionnaires, 20 key persons were interviewed with face-to-face conversation and 47 participants were involved in participatory rural assessment (PRA), transhumance characterized by the seasonal movements of livestock between different ecological belts is key grazing pattern in the case sites. Rotational grazing of the pasturelands according to feed availability is the example of deployment of indigenous knowledge adapted by local farmers. Cross breeding of yak with cattle (Tibetan cattle bull or Zebu cattle cow) is popular in traditional herd farming system. The breeding patterns in local yak farming systems reflect the seasonal availability and climatic variation, matching very well to transhumant grazing strategies. Supplementing the herd with a small amount of concentrates in harsh lean period is the traditional feeding management. F1 hybrid calf is carefully reared and F2 hybrid calf is killed by carelessly rearing is an indigenous practice to improve the herd productivity. Careful grazing management and herbal remedies for various diseases, pests and plant poisoning are good examples of indigenous knowledge in animal health care, although the interview and survey results indicate that most farmers believe their indigenous livestock managements are moderately efficient, there are still some problems and limitations for optimizing their yak and chauri management systems. More public supports are expected by local farmers to improve yak and chauri production systems, the potential indigenous industries in remote mountainous areas. It can be recommended and suggested from this case study that making better use of the vast indigenous knowledge that the local farmers possess is necessary when making improved management plans for yak and chauri farming system. Participatory research, policy-making and extension network should be developed to encourage the farmers to work together with professionals for better integrating the indigenous skills with advanced technologies. Indigenous institution development and farmers’ capacity building are imperative for better planning and successful implementation of livestock management program. Key words: Indigenous knowledge, yak and hybrids, management system.

Altitude dependence of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in surface soil from Tibetan Plateau, China

Remote mountain areas besides high latitude regions are beginning to receive increased attention in studying the transport and behavior of persistent organic pollutants (POPs). In the present work, surface soil samples were collected from the Tibetan Plateau, the highest plateau in the world which includes the northern slope of Mt. Qomolangma, to investigate the levels and trends of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) along the altitudinal gradient. The average PCB and PBDE concentrations were 185.6 ng kg −1 dry weight (dw) (range 47.1–422.6 ng kg −1 dw) and 11.1 ng kg −1 dw (range 4.3–34.9 ng kg −1 dw), respectively. Regression analysis between the log-transformed TOC-normalized concentrations and the altitudes of the sampling sites showed two opposite trends with regard to altitude dependence: negative relationship with altitude below about 4500 m followed by a positive altitude dependence above this point. Considering minimum anthropogenic activities and very sparse precipitation in the north of Himalayas, the trends above 4500 m imply that the significant altitude dependence of these two groups of POPs were irrespective of pollution sources, but could be predicted by the global distillation effect involving cold condensation in high altitude mountain areas. Increasing levels of heavier congeners were found in higher altitude sites, although the lighter congeners were the main contributors to the total amount, suggesting that less volatile congeners seem to become enriched easier than those more volatile at higher altitudes in this region.

Species‐level phylogeographical history of Myricaria plants in the mountain ranges of western China and the origin of M. laxiflora in the Three Gorges mountain region

Myricaria species in China occur mostly in the major high-altitude mountain areas in and around the Qinghai-Tibetan Plateau. The one major exception to this is M. laxiflora which is restricted to the Three Gorges mountain region. In this study, we investigate species-level phylogeographical patterns of Myricaria species in western China and the origin of M. laxiflora. The results show that most chloroplast haplotypes are species-specific, except for one haplotype which is shared by three widespread species. Higher haplotype diversity within the Qinghai-Tibetan Plateau region supports the hypothesis that the Himalayas are the centre of origin for Myricaria. The phylogeny of Myricaria was geographically structured, and an estimated Bayesian chronology suggested the main divergence events occurred during the Late Pliocene and Early Pleistocene (approximately 1.46-2.30 million years ago). The overall phylogeographical pattern was characterized by vicariance events and regional demographical expansion, reflecting a major influence of geological and climatic events on the evolution of Myricaria species. Our data suggest that M. laxiflora has an ancient origin, but has experienced recent population expansion through the Three Gorges Valley. The origin of M. laxiflora was estimated to be during the Early Pleistocene but its demographical expansion was more recent at about 0.015 million years ago. This highlights the unique phylogeographical history of the Three Gorges mountain region, and the deep imprint of the watercourse connections of the Yangtze River Valley on the phylogeographical structure of the species in this region.

Air-Gap Discharge Characteristics in Foggy Conditions Relevant to Lightning Shielding of Transmission Lines

The features of lightning shielding of transmission lines have been calculated using the electrogeometric model (EGM) proposed by Armstrong and Whitehead. Discrepancies, however, have been found in the case of ultra-high voltage (UHV)-designed transmission lines. UHV-designed transmission lines often pass through high-altitude mountain areas, where foggy or rainy conditions are common when there is lightning. While the electrogeometric model determines the striking distance based on the lightning stroke current, environmental conditions, and how they might affect lightning discharge paths, they are not considered. It is possible, therefore, that foggy conditions may cause differences in the performance of transmission-line lightning shielding. This study used scale models of transmission lines for discharge tests with a 1-m air gap and analyzed differences in discharge paths and locations in dry and foggy conditions. The results showed that the polarity of the discharge had a significant influence, but differences in dry and foggy tests were negligible.

MEDICINAL AND AROMATIC PLANTS IN ITALY: SITUATION AND PERSPECTIVE FOR THE PIEDMONT REGION

MEDICINAL AND AROMATIC PLANTS IN ITALY: SITUATION AND PERSPECTIVE FOR THE PIEDMONT REGION

Application of a power line maintenance information system using OPGW to the Nishi-Gunma UHV line

Tokyo Electric Power Company, Inc. began operation of the Nishi-Gunma UHV trunk line, the first 1000 kV designed power line in Japan, in April, 1992. This line is expected to be the key line in a major trunk-line system that is being developed. It traverses high-altitude mountainous areas subject to severe environmental and meteorological conditions for a long distance. A system using composite fiber-optic overhead ground wire (OPGW) is constructed to obtain precise information on this line for maintenance purposes. This system comprises three major functions: (1) meteorological and facility's monitoring for gathering meteorological data on such elements as winds, and icing and snow accretion, and for evaluating the corresponding reaction of the components such as conductor tension, and strain in the tower structure; (2) industrial TV monitoring for visual observation of weather, surrounding conditions and site facilities; and (3) fault section location for pinpointing faults quickly and determining the maintenance office that should respond to the faults. This is done by estimating the fault section accurately around the boundaries of the maintenance jurisdictions. This paper describes the development of these functions and results obtained from practical operation. >