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1.
Int J Mol Sci ; 25(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38396942

RESUMO

Environmental stress at high altitudes drives the development of distinct adaptive mechanisms in plants. However, studies exploring the genetic adaptive mechanisms of high-altitude plant species are scarce. In the present study, we explored the high-altitude adaptive mechanisms of plants in the Himalayas through whole-genome resequencing. We studied two widespread members of the Himalayan endemic alpine genus Roscoea (Zingiberaceae): R. alpina (a selfing species) and R. purpurea (an outcrossing species). These species are distributed widely in the Himalayas with distinct non-overlapping altitude distributions; R. alpina is distributed at higher elevations, and R. purpurea occurs at lower elevations. Compared to R. purpurea, R. alpina exhibited higher levels of linkage disequilibrium, Tajima's D, and inbreeding coefficient, as well as lower recombination rates and genetic diversity. Approximately 96.3% of the genes in the reference genome underwent significant genetic divergence (FST ≥ 0.25). We reported 58 completely divergent genes (FST = 1), of which only 17 genes were annotated with specific functions. The functions of these genes were primarily related to adapting to the specific characteristics of high-altitude environments. Our findings provide novel insights into how evolutionary innovations promote the adaptation of mountain alpine species to high altitudes and harsh habitats.


Assuntos
Altitude , Zingiberaceae , Himalaia , Genômica , Evolução Biológica , Adaptação Fisiológica/genética
2.
Mol Phylogenet Evol ; 164: 107292, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34391915

RESUMO

The Himalayas with dramatic elevation gradient is one of the global biodiversity hotspots. Although origin of biodiversity of the Himalayas is of great concern, the speciation process within the Himalayas is poorly known. Roscoea within the Himalayas serve as a good model system to test the speciation process along an elevation gradient. 32,375 unlinked SNPs were used to reconstruct phylogenetic relationships and introgression analyses in D-statistics and Fastsimicoal2. Species distribution modeling (SDM) was used to simulate habitat shift of Roscoea species during climate changes. Phylogeny suggested that the speciation order, except R. capitata, was from highland to lowland. D-statistics analyses suggested significant bidirectional ancient introgression between elevation-neighboring clades but no introgression between R. capitata and othern clades and no introgression among extant species. Fastsimicoal2 suggested interspecific introgressions were asymmetric. SDM predicted that habitats of Roscoea shifted to low elevation during cooling age. These results suggested that the sudden uplift of the Himalayas likely promoted speciation by vicariance, and climate cooling drove species divergence towards lower elevation. This study provides explanations for the origin of biodiversity within the Himalayas, and an insight to understand speciation along elevation in the mountainous regions.


Assuntos
Biodiversidade , Hidrozoários , Animais , Mudança Climática , Ecossistema , Especiação Genética , Filogenia
3.
J Environ Manage ; 295: 113101, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34198174

RESUMO

We simulated and analyzed the glacier dynamics over the Beas basin (situated in the north-western Himalayas) for the present (1980-2015) and future climates (2006-2100) under RCP4.5 and RCP8.5 global warming scenarios. We first calibrated the Open Global Glacier Model over the study region and then conducted simulations for the present (forced by ERA-Interim) and future (forced by CMIP5 models) climates. For the present climate, the model simulations show that 50% of the total glacier volume (compared to 1980) is lost by 2011, with glacier area and volume showing a significantly decreasing trend, with higher fluctuations in the glacial area during recent decades. Future projections suggest 75% loss by 2040 ± 2.5 years and ~90% loss by 2094 ± 3.5 years under RCP4.5. Under RCP8.5, 75% loss is expected to occur by 2040 ± 3 years and ~90% loss by 2084 ± 8 years. Ensemble mean of the near-surface air temperature (both monthly mean and annual mean) shows a significantly increasing trend under both RCP4.5 and RCP8.5 for the entire 21st century. Ensemble mean of the total monthly precipitation shows no trend under RCP4.5, however, it shows a decreasing trend for months ODJFMA and an increasing trend for months JJ under RCP8.5. An increase in JJ precipitation does not increase glacier mass since this region does not receive snowfall during these months. Under RCP4.5, snowfall does not show any significant trend during NDJF, however, it shows a decreasing trend during October and March. Under RCP8.5, snowfall shows a significant decreasing trend for October through March. Overall, we find similar melting rates under RCP4.5 and RCP8.5 until ~2050, but the latter shows a higher rate afterward.


Assuntos
Mudança Climática , Aquecimento Global , Clima , Temperatura
4.
BMC Ecol ; 19(1): 19, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046735

RESUMO

BACKGROUND: Species richness and composition pattern of amphibians along elevation gradients in eastern Nepal Himalaya are rarely investigated. This is a first ever study in the Himalayan elevation gradient, the world's highest mountain range and are highly sensitive to the effects of recent global changes. The aim of the present study was to assess amphibian community structure along elevation gradients and identify the potential drivers that regulate community structures. Amphibian assemblages were sampled within 3 months in both 2014 and 2015 (from May to July) using nocturnal time constrained and acoustic aids visual encounter surveys. In total, 79 transects between 78 and 4200 m asl were sampled within 2 years field work. A combination of polynomial regression, generalized linear models, hierarchical partitioning and canonical correspondence analysis were used to determine the effects of elevation and environmental variables on species richness, abundance, and composition of amphibian communities. RESULTS: Species richness and abundance declined linearly with increasing elevation, which did not support the Mid-Domain Model. Among all the environmental variables, elevation, surface area and humidity were the best predictors of species richness, abundance and composition of amphibians. The majority of amphibian species had narrow elevation ranges. There was no significant correlation between species range size and elevation gradients. However, body size significantly increased along elevation gradients, indicating that Bergmann's rule is valid for amphibians in eastern Nepal Himalaya. CONCLUSIONS: This study indicates that eastern Nepal Himalaya is a hotspot in amphibian diversity, and it should be served as a baseline for management and conservation activities.


Assuntos
Altitude , Biodiversidade , Anfíbios , Animais , Modelos Lineares , Nepal
5.
Conserv Biol ; 31(2): 416-426, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27558794

RESUMO

The impacts of land-use change on biodiversity in the Himalayas are poorly known, notwithstanding widespread deforestation and agricultural intensification in this highly biodiverse region. Although intact primary forests harbor many Himalayan birds during breeding, a large number of bird species use agricultural lands during winter. We assessed how Himalayan bird species richness, abundance, and composition during winter are affected by forest loss stemming from agriculture and grazing. Bird surveys along 12 elevational transects within primary forest, low-intensity agriculture, mixed subsistence agriculture, and intensively grazed pastures in winter revealed that bird species richness and abundance were greatest in low-intensity and mixed agriculture, intermediate in grazed pastures, and lowest in primary forest at both local and landscape scales; over twice as many species and individuals were recorded in low-intensity agriculture than in primary forest. Bird communities in primary forests were distinct from those in all other land-use classes, but only 4 species were unique to primary forests. Low-, medium-, and high-intensity agriculture harbored 32 unique species. Of the species observed in primary forest, 80% had equal or greater abundance in low-intensity agricultural lands, underscoring the value of these lands in retaining diverse community assemblages at high densities in winter. Among disturbed landscapes, bird species richness and abundance declined as land-use intensity increased, especially in high-intensity pastures. Our results suggest that agricultural landscapes are important for most Himalayan bird species in winter. But agricultural intensification-especially increased grazing-will likely result in biodiversity losses. Given that forest reserves alone may inadequately conserve Himalayan birds in winter, comprehensive conservation strategies in the region must go beyond protecting intact primary forests and ensure that low-intensity agricultural lands are not extensively converted to high-intensity pastures.


Assuntos
Agricultura , Aves , Conservação dos Recursos Naturais , Animais , Biodiversidade , Ecossistema , Florestas
6.
Telemed J E Health ; 22(10): 821-835, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27135412

RESUMO

INTRODUCTION: Nonavailability of quality healthcare in mountainous, isolated, inaccessible sparsely populated regions is a universal problem. In this project, remote virtual healthcare was provided at Keylong and Kaza in Himachal Pradesh (HP) in North India. This innovative public-private partnership (PPP) provides 24/7 affordable healthcare to an alpine community where people commute 20-50 km for primary and 250 km for secondary healthcare services. Following a need assessment study, an MoU was signed by Apollo Hospitals in January 2015 with the National Health Mission. The government paid for all services delivered, Capital Expenditure (CAPEX) and Operating Expenditure (OPEX). Noncompliance to auditable weekly and monthly program MIS would result in penalties. METHODS: Apollo Telehealth Services customized a turnkey solution, end-to-end, on a program management approach with measurable milestones and monthly reports. Key health issues in the region were identified. Very Small Aperture Terminals were installed amidst landslides and subzero temperatures. In February and March 2015, staff recruited from the community and local government staff were trained in Chennai. A major cultural transformation had to be effected. Urban teleconsultants were sensitized for community interaction, while deploying cutting- edge technology. RESULTS: Case records were audited. In the first 42 weeks, 2,213 teleconsults were provided, including 171 emergencies. Telelaboratory services and telehealth education programs have also been added. CONCLUSIONS: Evaluation confirms that delivering remote healthcare in inhospitable terrains in a PPP mode is effective.


Assuntos
Parcerias Público-Privadas/organização & administração , Serviços de Saúde Rural/organização & administração , Telemedicina/organização & administração , Análise Custo-Benefício , Competência Cultural , Serviços Médicos de Emergência/organização & administração , Humanos , Índia , Avaliação das Necessidades , Satisfação do Paciente , Parcerias Público-Privadas/economia , Serviços de Saúde Rural/economia , Telemedicina/economia , Telemetria
7.
Environ Pollut ; 318: 120885, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36529339

RESUMO

Black carbon (BC) can be transported over long distances and is an important trigger of climate warming and glacier melting at remote high mountains and polar regions. It is normally assumed that the variation of BC flux in remote regions is dominated by its emissions. However, after a comprehensive investigation of potential influencing factors on temporal variations of BC from ice cores of the Himalayas, this short communication shows that in addition to BC emissions, contributions from dust storms and precipitation are also important (up to 56% together) in regulating the variation of BC deposition flux and concentrations derived from remote Himalayan ice core measurements. Therefore, besides BC emissions, the influence of precipitation and BC transported by dust storms should also be considered to better quantify the lifetime and behavior of BC during its long-range transport from source to sink regions as well as to quantify the climatic effects of BC over remote Himalayan glaciers.


Assuntos
Monitoramento Ambiental , Camada de Gelo , Carbono/análise , Fuligem/análise , Poeira/análise
8.
FEMS Microbiol Ecol ; 99(9)2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37562924

RESUMO

Arbuscular mycorrhizal (AM) fungi can benefit plants under environmental stress, and influence plant adaptation to warmer climates. However, very little is known about the ecology of these fungi in alpine environments. We sampled plant roots along a large fraction (1941-6150 m asl (above sea level)) of the longest terrestrial elevational gradient on Earth and used DNA metabarcoding to identify AM fungi. We hypothesized that AM fungal alpha and beta diversity decreases with increasing elevation, and that different vegetation types comprise dissimilar communities, with cultured (putatively ruderal) taxa increasingly represented at high elevations. We found that the alpha diversity of AM fungal communities declined linearly with elevation, whereas within-site taxon turnover (beta diversity) was unimodally related to elevation. The composition of AM fungal communities differed between vegetation types and was influenced by elevation, mean annual temperature, and precipitation. In general, Glomeraceae taxa dominated at all elevations and vegetation types; however, higher elevations were associated with increased presence of Acaulosporaceae, Ambisporaceae, and Claroideoglomeraceae. Contrary to our expectation, the proportion of cultured AM fungal taxa in communities decreased with elevation. These results suggest that, in this system, climate-induced shifts in habitat conditions may facilitate more diverse AM fungal communities at higher elevations but could also favour ruderal taxa.


Assuntos
Glomeromycota , Micorrizas , Micorrizas/genética , Simbiose , Ecossistema , Raízes de Plantas/microbiologia , Clima , Plantas , Microbiologia do Solo , Solo
9.
Sci Total Environ ; 832: 155020, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35381240

RESUMO

As an important component of carbonaceous aerosols (CA), organic carbon (OC) exerts a strong, yet insufficiently constrained perturbation of the climate. In this study, we reported sources of OC based on its natural abundance radiocarbon (14C) fingerprinting in aerosols and water-insoluble organic carbon (WIOC) in snowpits across the Tibetan Plateau (TP) - one of the remote regions in the world and a freshwater reservoir for billions of people. Overall, the proportions from 14C-based non-fossil fuel contribution (fnon-fossil) for OC in aerosols was 74 ± 10%, while for WIOC in snowpits was 81 ± 10%, both of which were significantly higher than that of elemental carbon (EC). These indicated sources of OC (WIOC) and EC were different at remote TP. Spatially, high fnon-fossil of WIOC of snowpit samples appeared at the inner part of the TP, indicating the important contribution of local non-fossil sources. Therefore, local non-fossil sources rather than long-range transportation OC dominants its total amount of the TP. In addition, the contribution of local non-fossil sourced WIOC increased during the monsoon period because heavy precipitation removed a high ratio of long-range transportation WIOC. The results of this study showed that not only OC and EC but also their different fuel sources should be treated separately in models to investigate their sources and atmospheric transportation.


Assuntos
Poluentes Atmosféricos , Carbono , Aerossóis/análise , Poluentes Atmosféricos/análise , Atmosfera , Carbono/análise , Monitoramento Ambiental/métodos , Humanos , Camada de Gelo , Material Particulado/análise , Estações do Ano , Tibet , Água
10.
Integr Zool ; 17(5): 715-730, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35060680

RESUMO

Tens of thousands of demoiselle cranes' crossing the Himalayas to the Indian subcontinent have been reported for decades, but their exact spring migration route remained a mystery until our previous study found they made a detour in spring along the western edge of the Himalayas and crossed the Mongolian Plateau to their breeding areas based on satellite telemetry of 3 birds. To corroborate the loop migration pattern and explore whether demoiselle crane's loop migration route is shaped by time- and energy-minimization strategies in spring and autumn and how the temporal and spatial variation of environmental conditions contribute to crane's selection of migration routes, we tracked 11 satellite-tagged demoiselle cranes from their breeding area in China and Russia, simulated 2 pseudo migration routes, and then compared the environmental conditions, time, and energy cost between true and pseudo routes in the same season. Results show that demoiselles' spring migration obeyed time-minimization hypothesis, avoiding the colder Qinghai-Tibet Plateau, benefited by abundant food and higher thermal and orographic uplift along the route; autumn migration follows energy-minimization hypothesis with the shorter route. Our research will contribute to uncover the mechanical reasons why demoiselle crane avoids crossing the giant barrier of the Himalayas in spring, and shapes a loop migration route.


Assuntos
Migração Animal , Aves , Animais , China , Estações do Ano , Telemetria
11.
PhytoKeys ; 153: 13-35, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765178

RESUMO

Begonia is a mega-genus with about 2500 species by most estimates, with China having over 210 accepted species. After field surveys, literature review and examination of herbarium specimens, some new taxa, new records, synonyms and the hybrid-origin of some taxa have been confirmed. Here, we report that Begonia dioica Buch.-Ham. ex D.Don and B. flagellaris Hara, both from Xizang (Tibet) are new to China; Begonia lipingensis Hance, B. muliensis T.T.Yu and B. sizemoreae Kiew are synonyms of B. circumlobata Hance, B. taliensis Gagnepain and B. longiciliata C.Y.Wu, respectively; and Begonia × lancangensis S.H.Huang and B. × malipoensis S.H.Huang & Y.M.Shui are natural hybrids.

12.
Environ Sci Pollut Res Int ; 27(3): 2670-2676, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31836975

RESUMO

At present, the glaciers in the Himalayas and the Tibetan Plateau (HTP) are retreating partly due to albedo reduction caused by deposited light-absorbing impurities such as mineral dust (MD) and black carbon (BC). Because BC also exists widely in MD from surface soil, it is necessary to further evaluate the contribution of BC from MD to the total BC at glacier region. This will help to improve the study of BC sources by considering the relative contributions from MD and direct combustion sources. Therefore, in this study, concentrations of total organic carbon (TOC) and fine particles of BC from 43 surface soil samples of the HTP were investigated. The contribution of BC from MD to total BC deposited at the glacier region was evaluated. The results showed strong correlations between TOC and BC of studied samples (R2 = 0.70, p < 0.01), suggesting that they have similar sources and activity characteristics. The average BC concentration of studied samples was 2.02 ± 1.55 mg g-1, much lower than those of particles deposited at the glacier region and other regions with high soil TOC concentration. The contributions of BC from MD to total surface BC at two glaciers of the inner HTP (Zhadang and Xiaodongkemadi) were 17.66 ± 10.84% and 20.70 ± 16.35%, respectively. Therefore, the contribution of MD to glacier melting of the HTP is higher than that of previously assumed after BC coming along with MD is considered. Because MD concentration is higher at north and west part of the HTP, the contributions of MD at these glacier regions should be larger than previously assumed.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Solo , Fuligem/análise , Carbono , Camada de Gelo , Tibet
13.
Zootaxa ; 4344(2): 380-386, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29245640

RESUMO

The neotenic click-beetle genus Selasia Laporte, 1838 is distributed mainly in the tropical Africa, and only a few species are known from the Palaearctic and Oriental regions. Herein, I describe and figure two new Palaearctic species: Selasia nigrobrunnea sp. nov. from the western Nepal, and Selasia sabatinellii sp. nov. from Pakistan. Both species are compared with their Palaearctic congeners, and an updated identification key to Selasia species from the Palaearctic region is provided.


Assuntos
Besouros , África , Distribuição Animal , Animais , Nepal , Paquistão
14.
Sci Total Environ ; 598: 307-318, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28448923

RESUMO

The Tibetan Plateau (TP) plays important roles in global climate and environment. This study combines in-situ BC measurements in the Himalayas and the Indo-Gangetic Plain (IGP) with a regional dynamical and chemical model (WRF-Chem model) to investigate the effect of the trans-Himalayas on black carbon (BC) from the IGP to the TP during Indian summer monsoon. To determine topographic effects of the trans-Himalayas on BC concentrations over the TP, sensitive experiments were conducted by applying the WRF-Chem model. The results showed that the reduction of the altitude of the Himalayas had an important effect on the trans-Himalayas transport of BC. There was an obvious increase in BC concentration over the trans-Himalayas region, but no significant increase over the TP because the TP (a.m.s.l ~4km) always acted as a wall to prevent BC transport from the IGP to the TP. The trans-Himalayas transport of BC was strongly dependent upon meteorological conditions over the IGP. During summer monsoon, there were three types of cyclones at different locations and one kind of convergent circulation in the IGP. Under the condition of convergent airflows, a strong northeastward wind produced the trans-Himalayas transport of BC. As a result, BC concentrations in the southeastern TP significantly increased to 0.6-0.8µgm-3. When the cyclone located in the eastern IGP, high BC concentrations over the IGP were transported along the foothill of the Himalayas, resulting in a significant reduction of the trans-Himalayas transport. When the cyclone moved to the west, the dynamical perturbations for the trans-Himalayas transport were weaker than the eastern cyclone, and the trans-Himalayas transport were enhanced in the middle and eastern Himalayas. This study will be helpful to assess the impacts of BC particles emitted from South Asia on regional climate change and ecological environment over the TP in the future.

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