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1.
Environ Monit Assess ; 196(10): 925, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39264478

RESUMEN

This is the first report on high pesticide tolerance displayed by the microbiota isolated from the sediments of two high-altitude lakes, located in the Singalila National Park, Singalila Ridge of the Himalayas. Given the remote location of these lakes, direct exposure to chemical pesticides is highly unlikely. However, the high tolerance to commonly used pesticides exhibited, i.e. up to 250 mg/ml, suggests repeated exposure and contamination of the lakes. Microbial growth in the presence of varying concentrations of the pesticides, namely, emamectin benzoate, thiamethoxam, quinalphos, deltamethrin, spiromesifen, flubendiamide, monocrotophos, fipronil, fenazaquin and phorate, was tested. Results showed resistance to all pesticides except fenazaquin and fipronil, up to 250 mg/ml. For the latter two, tolerance was displayed up to a concentration of 40 mg/ml. Tolerance may potentially result from the transport and deposition of pesticides from nearby locations, particularly the tea plantations of Darjeeling and Eastern Nepal. This may create great ecological risks as these lakes are an important water source for endemic wildlife of this protected area. They also hold great significance to the religious sentiment of the local tribes who worship these lakes as sacred. The study highlights the need for monitoring pesticide contamination in such pristine high-altitude environments and the mechanisms of long-range pollutant transport.


Asunto(s)
Altitud , Monitoreo del Ambiente , Lagos , Plaguicidas , Contaminantes Químicos del Agua , Lagos/microbiología , Lagos/química , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Nepal , Nitrilos/toxicidad , Microbiota/efectos de los fármacos , Piretrinas , Himalayas , Ivermectina/análogos & derivados
2.
Heliyon ; 10(16): e36211, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39247288

RESUMEN

Springs and streams are vital water sources for supporting the livelihood of Himalayan residents. Escalating climate change, population growth, and economic development strain the region's freshwater resources. A national survey reveals declining spring and stream flows in Bhutan, necessitating an improved understanding of their generation. Monthly grab water samples were collected during April 2022-January 2023 from main streams, springs and other source waters at various elevations at Yude Ri and Dungju Ri catchments, Bhutan Himalayas. Samples were analyzed for pH, specific conductance, and major ions and end-member mixing analysis in combination with diagnostic tools of mixing models was used to determine sources, relative contributions, and recharge dynamics of spring flows. The results indicated that direct precipitation dominated spring flows (0.59 ± 0.21), followed by shallow groundwater (0.31 ± 0.18), and soil subsurface water (0.10 ± 0.15). The contributions of spring flow components followed an elevation gradient, with higher and lower fractions, respectively, of direct precipitation and shallow groundwater at higher elevations, e.g., 0.90 ± 0.1 to 0.13 ± 0.08 for direct precipitation and 0.03 ± 0.03 to 0.37 ± 0.19 for shallow groundwater from 3266 m to 1558 m. Spring flows primarily relied on precipitation (∼70 % from both direct precipitation and soil water), making them very sensitive to changes in precipitation. Significant contributions of shallow groundwater also indicated the vulnerability of spring flows to decreased snowfall relative to rainfall and the earlier onset of snowmelt, particularly for those located in the snow-rain transition zone (∼2500 m). Our results suggest high vulnerability of spring flows to the climate change in the Himalayas.

3.
Environ Monit Assess ; 196(10): 913, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39254782

RESUMEN

Soil efflux of CO2 ( F CO 2 ) is known to be dependent on natural drying and rewetting of the soil. Although the central Indian Himalayan region is predominantly occupied with two ecosystems, i. e. Pine (Pinus roxburghii) and Oak (Quercus leucotrichophora), differences in their F CO 2  dynamics and responses of F CO 2  to varying wet and dry spells were hardly known. To address this knowledge gap, this study provides a comparative assessment of F CO 2  variability from Pine and Oak ecosystems of central Himalaya as a response to rainfall induced wet and dry spells of monsoon and winter seasons. The F CO 2  data presented in this study are collected for 242 days of 2021-22 that include monsoon and winter seasons from a Pine and an Oak sites. The mean F CO 2 s of Pine and Oak sites are found to be 3.95(± 0.02) and 3.61(± 0.01) µmol.m-2.s-1, respectively. We find that the winter reduction in the F CO 2  in comparison to monsoon at the Pine site (78%) is more substantial than at Oak site (64.6%). The cross wavelet spectra of F CO 2  and monsoon rainfall amount at the Oak site, unlike the Pine site, indicate a negative relationship. The rainfall spell duration and amount of monsoon wet spells are noted to have an inverse relationship with F CO 2  at both sites, although, increasing rainfall spell duration in winter is noted to increase F CO 2  at Pine and Oak sites. Similarly, increasing F CO 2  is observed with increasing dry spells of monsoon at both sites. Results of this study indicate that in comparison to Oak, F CO 2  variability at Pine ecosystem is primarily driven by abiotic factors wherein wet spell is a major determinant.


Asunto(s)
Dióxido de Carbono , Ecosistema , Monitoreo del Ambiente , Pinus , Quercus , Lluvia , Estaciones del Año , Suelo , Suelo/química , Dióxido de Carbono/análisis , India
4.
Ann Med Surg (Lond) ; 86(9): 4975-4978, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39239017

RESUMEN

Introduction: Mad honey is commonly used for hypertension, and coronary artery disease, and as a sexual stimulant. Patients with mad honey poisoning present with dizziness, nausea, syncope, blurred vision, bradycardia, and hypotension with ECG findings of sinus bradycardia, complete AV block, and ST elevation. Case discussion: Here, the authors report five cases admitted to our tertiary care center following the consumption of mad honey. The amount of ingestion of honey varies from 1 to 2 teaspoons (~10-20 ml). Most of the cases presented with chief complaints of nausea, dizziness, and vomiting, and all the cases had hypotension and bradycardia. Two cases were admitted to the ward and three of them were admitted to the ICU for further management. They were managed with intravenous fluid, injection atropine along with adjunctive vasopressor and oxygen whenever necessary. Discussion: Mad honey contains grayanotoxin extracted from the nectar of Rhododendron species. This honey contains grayanotoxin, which binds to sodium channels in its open state causing hyperpolarization of the sodium channel predominantly causing gastrointestinal, neurological, and respiratory symptoms. Intravenous fluids and injection atropine are the mainstays of management in an ICU setup. Some also may require vasopressors. Conclusion: Mad honey poisoning is rare, and limited cases have been reported in Nepal. Physicians should consider mad honey poisoning in cases with ingestion history and clinical symptoms, as it may be a clinical diagnosis due to limited lab tests for grayanotoxin intoxication. Supportive management still forms the cornerstone for its management after diagnosis.

5.
Heliyon ; 10(17): e36571, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39263057

RESUMEN

The species of the subfamily Polygonoideae is an essential component of temperate forests as well as the flora of the western Himalayan region. The aim of this research was to explore the taxonomic diversity, distribution patterns, and associated flora of Polygonoideae in relation to edaphic factors in various ecological zones in the Muzaffarabad division of the Kashmir Western Himalayan Region. We applied a random sampling approach for data collection from 10 different sites with a cumulative 780 quadrats to record the diversity of wild Polygonoideae species across the Muzaffarabad division between 2021 and 2022. This study revealed 279 plant species from 192 genera and 75 families associated with Polygonoideae, with the dominant families being Asteraceae, Poaceae, Lamiaceae, and Rosaceae. Herbs were predominant in the investigated area, with a proportion of 72.40 %, followed by shrubs (9.68 %) and pteridophytes (8.24 %). The flora was dominated by therophytes (37.35 %), whereas nanophylls (37.28 %) were the most dominant leaf form. Persicaria, Rumex, and Polygonum genera were observed and collected from various ecological zones, while Bistorta, Fagopyrum, Oxyria, and Rheum were only collected from a single zone, representing a restricted niche. A total of 28 taxa from 8 genera were studied in the investigative subfamily Polygonoideae, with the majority being therophytes (57.14 %), followed by hemicryptophytes (28.57 %), and leaf form dominated by microphylls (50 %) and nanophylls (17.85 %). The average values for Shannon and Simpson's diversity for the reported plant communities were 0.96 and 3.53, respectively, whereas species richness averaged 2.43 and species evenness 0.92. The vegetation exhibited a relatively lower (<50) maturity, averaging 32.08. Deforestation, overexploitation for medicinal purposes, soil erosion, overgrazing, forest fires, and the expansion of agricultural fields were identified as major threats to floral diversity. A significant correlation was observed between elevation and soil nutrient parameters, where moisture content, SOC, SOM, TK, and TN ratios showed a positive correlation, while pH and TP showed a negative correlation. Polygonum paronychioides and Rumex alpinus were the least observed of Polygonoideae taxa, whereas 39 species were found to be threatened, having low (<0.2) IVI values and seeking immediate conservation efforts. Climate change and anthropogenic pressure may lead to a change in the composition patterns and threaten the Polygonoidae species. We suggest community-based initiatives and sustainable conservation measures to safeguard the floral wealth of the Western Himalaya.

6.
Animals (Basel) ; 14(16)2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39199959

RESUMEN

Limited background data are available on the Mishmi takin (Budorcas taxicolor taxicolor) and Bhutan takin (Budorcas taxicolor whitei) subspecies in the Eastern Himalayas of China because of the lack of systematic field investigations and research. Therefore, mature-animal ecological methods were used to evaluate these takin subspecies' phenotypic characteristics, distribution range, activity rhythm, and population size. From 2013 to 2022, 214 camera traps were installed for wild ungulate monitoring and investigation in all human-accessible areas of the Eastern Himalayas, resulting in 4837 distinguishable takin photographs. The external morphological characteristics were described and compared using visual data. Artificial image correction and related technologies were used to establish physical image models based on the differences between subspecies. MaxEnt niche and random encounter models obtained distribution ranges and population densities. Mishmi takins have a distribution area of 17,314 km2, population density of 0.1729 ± 0.0134 takins/km2, and population size of 2995 ± 232. Bhutan takins have a distribution area of 25,006 km2, population density of 0.1359 ± 0.0264 takins/km2, and population size of 3398 ± 660. Long-term monitoring data confirmed that the vertical migration within the mountain ecosystems is influenced by climate. Mishmi takins are active at 500-4500 m, whereas Bhutan takins are active at 1500-4500 m. The two subspecies were active at >3500 m from May to October yearly (rainy season). In addition, surveying combined with model simulation shows that the Yarlung Zangbo River is not an obstacle to migration. This study provides basic data that contribute to animal diversity knowledge in biodiversity hotspots of the Eastern Himalayas and detailed information and references for species identification, distribution range, and population characteristics.

7.
Wilderness Environ Med ; 35(3): 308-313, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39095053

RESUMEN

The Himalayan Rescue Association (HRA) has operated high altitude clinics in Nepal for 50 years, with rising visitor numbers, especially from India, China, and Nepal. New roads have eased access and increased the speed of ascent in some areas. Our aim was to provide a description of the activities, clinical problems, and lecture attendees of the HRA aid post in Manang over one season. We also highlight the evolving challenges of providing healthcare and education in the high Himalayan region. We describe the clinical and educational activities of the HRA aid post in Manang from September 24 to December 1, 2023. Prospective clinical data collection included anonymized patient demographics and diagnoses. Lecture data were taken from the attendee register and by daily manual counts of lecture attendees. We saw 376 patients, 62% of whom were Nepalis. Infectious diseases (42%) and altitude illness (16%) were the most common problems. A total of 846 people from 47 countries attended the daily altitude lectures. Only 5% of attendees were Nepali. Electrical supply interruptions and limitations in medical evacuation options were among the challenges of providing care at a high altitude clinic and preventing altitude illness using educational lectures. Altitude illness remains a common and potentially life-threatening problem, with risks increased by rapid ascent enabled by new road access and by ignorance of risks of altitude among travelers, especially Nepalis. Language barriers in educational outreach call for novel approaches and interventions that will ensure the effectiveness of altitude education.


Asunto(s)
Mal de Altura , Montañismo , Trabajo de Rescate , Nepal , Humanos , Mal de Altura/epidemiología , Mal de Altura/prevención & control , Adulto , Persona de Mediana Edad , Masculino , Femenino , Estudios Prospectivos , Adulto Joven
8.
Ambio ; 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39215932

RESUMEN

Longitudinal assessment of climate vulnerability is essential for understanding the complex factors affecting how people experience and respond to climate change. We report on the first longitudinal assessment of climate vulnerability in the Himalayan region, exploring the evolving landscape, perceptions, and experiences of communities of climate change impacts, vulnerability, and adaptation in Kashmir over an 8-year period from 2017 to 2024. We provide the Himalayan Re-study Framework (HRF) to monitor, characterise, and conceptualise climate change in the Himalayas. Utilising mixed methods, we showcase how climate change is affecting social, economic, political, and environmental dimensions, examining how the impacts of climate change and vulnerability evolve over time, shaping and reshaping how climate risks are experienced and responded to by communities. Our analysis reveals a nuanced understanding of vulnerability, highlighting the impact on communities' livelihoods and water security, differential impacts on marginalised communities, and the gendered nature of climate change. We examine how certain sections of the population face marginalisation, discrimination, and racism, and how climate change exacerbates these challenges. Kashmir's vulnerability to climate change extends beyond environmental factors, intertwining with culture, livelihoods, social dynamics, and politics. Climate change continues to compete for attention with immediate political and socio-economic challenges, highlighting the need for integrated approaches to address both environmental and societal issues in Kashmir.

9.
Sci Total Environ ; 949: 175147, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39084375

RESUMEN

Water-soluble ions, inorganic nitrogen, and stable isotopes in precipitation were assessed from the southern (Koshi Tappu and Khandbari) and northern slopes (Lhasa and SET) of the Himalayas to understand the sources, chemistry of regional precipitation, and climatic processes. Water soluble ions showed distinct seasonal variation, with higher concentrations in the non-monsoon. The concentration of ionic species was highest in Koshi Tappu, followed by Lhasa, SET, and Khandbari. The sources were from the terrigenous (Ca2+, HCO3-), marine (Na+ and Cl-), anthropogenic (SO42-, NO3-, and NH4+), terrigenous and marine (Mg2+), and biomass-burning (K+). The southern slope, relative to the northern, was more prone to anthropogenic emissions with higher deposition. Among all sites, inorganic nitrogen deposition at Koshi Tappu was higher than the threshold value (10 kg ha-1 y-1). The isotopic composition during the study period was higher in non-monsoon, started declining from June, and depleted in July and August compared to other months, i.e., the monsoon mature phase, along the south-to-north transect. The diminished value of stable isotopes in precipitation with increasing altitude underlines the evidence of the orographic effect in isotopic composition. Our study delineated that the higher/lower d-excess value increased with altitude on the southern/northern slope of the Himalayas. The backward trajectory analysis and the National Centers for Environmental Prediction's Final (NCEP FNL) datasets identified that most of the trajectories arrived from warm and humid low-latitude regions during monsoon and westerlies in non-monsoon. Thus, the chemical characteristics and stable isotopic composition of precipitation differed on the southern and northern slopes of the Himalayas by orographic effect and various sources. This study provides new insights into the atmospheric environment and climatic control of stable isotopes in the Himalayan Tibetan Plateau and facilitates monitoring of transboundary air pollution.

10.
Waste Manag Res ; : 734242X241262000, 2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39069718

RESUMEN

Non-governmental organizations (NGOs) play a critical role in addressing solid waste management (SWM) challenges in remote mountain communities, including the ecologically fragile Himalayan region. This study evaluates the impact of Healing Himalayas, an NGO, in Rakchham village, Himachal Pradesh, India. The objectives were to evaluate the effectiveness of Healing Himalayas' decentralized SWM model in promoting stakeholder engagement and resource recovery, assess the role of collaborations between local authorities and the NGO in financing waste management practices, investigate the influence of tourism and seasonal variations on solid waste generation patterns and waste management practices in Rakchham, and material recovery facilities, followed by glass (36.7%), paper/cardboard (18.4%) and metal (4.1%). A fee-based system involving the local village council funded waste operations. Waste generation exhibited significant seasonal fluctuations, with tourism influxes driving increased volumes. Healing Himalayas' initiatives promoted community participation, with over 15 awareness workshops conducted. Key challenges included limited financial resources, inadequate infrastructure, lack of advanced treatment facilities and need for context-specific solutions like efficient wet waste management in cold climates. The study highlights Healing Himalayas' decentralized model's success in fostering stakeholder engagement, behavioural change and resource recovery. The findings inform effective strategies for NGO-led waste management initiatives tailored to remote Himalayan communities.

11.
Sci Total Environ ; 948: 174701, 2024 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-38997012

RESUMEN

Holistic study of glacial lakes and glacial lake outburst floods (GLOFs) in the strategically important China-Nepal transportation corridors is imperative for regional connectivity and disaster risk reduction. This study focuses on four China-Nepal transportation corridors, namely Chentang-Kimathanka, Zhangmu-Kodari, Keyrung-Kathmandu and Taklakot-Hilsa from east to west in the Himalayan region. Within a remote integrated framework, we present the latest high-resolution inventory of glacial lakes, assess their decadal spatio-temporal changes (1992-2022), identify potentially dangerous glacial lakes, and apply hydrodynamic model to assess downstream impacts of possible GLOFs along the study area. The results show 2688 glacial lakes (≥0.001 km2) with a total area of 116.10 ± 8.53 km2 over the study area in 2022. Glacial lakes exhibited spatiotemporal heterogeneity in expansion, with overall expansion of 32 % during 30 years. Keyrung-Kathmandu corridor, among others, was assessed with high GLOF susceptibility. Furthermore, hydrodynamic modeling of four highly dangerous lakes in each transportation area reveals that GLOFs have cross-border effects, impacting ∼103 km of China-Nepal highway, 103 bridges, two major dry ports and 3301 buildings in both countries. Based on these findings, we emphasize the joint efforts of both countries for integrated disaster management for smooth connectivity between two countries and saving downstream population through joint cooperation from central to local government levels by initiating artificial lake lowering, developing cross-border early warning systems and cooperation. This study is valuable for presenting a synergistic study of glacial lakes and GLOF for informing decision- and policy-makers of both China and Nepal for a joint approach to disaster mitigation.

12.
J Hazard Mater ; 476: 135073, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38968826

RESUMEN

This study conducted a comprehensive analysis of trace element concentrations in the Upper Indus River Basin (UIRB), a glacier-fed region in the Western Himalayas (WH), aiming to discern their environmental and anthropogenic sources and implications. Despite limited prior data, 69 samples were collected in 2019 from diverse sources within the UIRB, including mainstream, tributaries, and groundwater, to assess trace element concentrations. Enrichment factor (EF) results and comparisons with regional and global averages suggest that rising levels of Zn, Cd, and As may pose safety concerns for drinking water quality. Advanced multivariate statistical techniques such as principal component analysis (PCA), absolute principal component scores (APCS-MLR), Monte Carlo simulation (MCS), etc were applied to estimate the associated human health hazards and also identified key sources of trace elements. The 95th percentile of the MCS results indicates that the estimated total cancer risk for children is significantly greater than (>1000 times) the USEPA's acceptable risk threshold of 1.0 × 10-6. The results classified most of the trace elements into two distinct groups: Group A (Li, Rb, Sr, U, Cs, V, Ni, TI, Sb, Mo, Ge), linked to geogenic sources, showed lower concentrations in the lower-middle river reaches, including tributaries and downstream regions. Group B (Pb, Nb, Cr, Zn, Be, Al, Th, Ga, Cu, Co), influenced by both geogenic and anthropogenic activities, exhibited higher concentrations near urban centers and midstream areas, aligning with increased municipal waste and agricultural activities. Furthermore, APCS-MLR source apportionment indicated that trace elements originated from natural geogenic processes, including rock-water interactions and mineral dissolution, as well as anthropogenic activities. These findings underscore the need for targeted measures to mitigate anthropogenic impacts and safeguard water resources for communities along the IRB and WH.

13.
Sci Total Environ ; 946: 174435, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38964402

RESUMEN

The retreat of Himalayan glaciers and the expansion of glacial lakes due to global warming have increased the occurrence of glacial lake outburst debris flow (GLODF), posing a serious threat to downstream communities. However, there are gaps in understanding the changes in GLODF occurrence driven by climate change, which challenges disaster management and cross-border cooperation in the Himalayas. To consider this issue, our study presents a novel framework integrating environmental evolution, a process-driven indicator system, and a hybrid machine learning model to predict Himalayan GLODF occurrence in the 21st century. Our findings indicate ongoing temperature (0.27-0.60 °C/10a) and precipitation (1.30-5.00 %/10a) increases under both SSP245 and SSP585 scenarios. Meanwhile, Himalayan glaciers are projected to lose between 70 % and 86 % of their mass by 2100 compared to 2020. Additionally, 2722 ± 207 new glacial lakes are expected to emerge by 2100. GLODF occurrence probability index is anticipated to rise to 1.27-1.30 times the current levels, with the Western Himalayas and Indus basin as high-incidence areas. Currently and in the future, the China-Nepal border remains a hotspot for cross-border GLODF. Our framework offers valuable long-term insights into Himalayan GLODF occurrence trends in response to climate change.

14.
J Forensic Sci ; 69(5): 1918-1925, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38992862

RESUMEN

Cannabis is one of the most consumed illicit drugs and the potency of cannabis products is of note due to health-related concerns. Hand-rubbed hashish is the ancient technique of extracting psychoactive resin from cannabis plants and is practiced in the Indian Himalayas. This study establishes the cannabinoid profile and potency of hand-rubbed hashish collected from 20 regions of the northwest Himalayas. Fifty-eight hashish samples were analyzed using a validated high-performance liquid chromatography-diode array detection (HPLC-DAD) method. Ten cannabinoids were quantified including acidic (THCA & CBDA), and neutral compounds (CBDV, THCV, CBD, CBG, CBN, Δ9-THC, Δ8-THC, and CBC). The mean concentration (w/w%) of Δ9-THC is 26%; THCA is 15% and THCTotal is 40% is observed in the studied hashish samples. The majority (70%) of the hashish samples were categorized in chemotype I with the THC:CBD:CBN ratio of 91:3:4, and the remaining 30% were categorized under chemotype II with the ratio of 76:15:8. Diverse qualities of hashish are produced in the studied regions as per the seed, plant selection, and skills of manual rubbing, which results in potency variations. The average difference between the least and highest potent hand-rubbed hashish of a region is 27 w/w% (THCTotal). The other studied non-psychoactive cannabinoids have a mean w/w% of <5%, followed by 6% of CBDA. It is concluded that the cultivated and wild cannabis fields in the northwest Himalayas belong to the drug-type cannabis subspecies. Hand-rubbed hashish holds traditional significance and impacts the current policies of legislation.


Asunto(s)
Cannabinoides , Cannabis , India , Cannabis/química , Cannabinoides/análisis , Humanos , Cromatografía Líquida de Alta Presión , Resinas de Plantas/química , Himalayas
15.
Am J Bot ; 111(8): e16334, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38825815

RESUMEN

PREMISE: Cytogenetic traits such as an organism's chromosome number and genome size are taxonomically critical as they are instrumental in defining angiosperm diversity. Variations in these traits can be traced to evolutionary processes such as polyploidization, although geographic variations across cytogenetic traits remain underexplored. In the pantropical monocot family Zingiberaceae (~1500 species), cytogenetic traits have been well documented; however, the role of these traits in shaping taxonomic diversity and biogeographic patterns of gingers is not known. METHODS: A time-calibrated Bayesian phylogenetic tree was constructed for 290 taxa covering three of the four subfamilies in Zingiberaceae. We tested models of chromosome number and genome size evolution within the family and whether lineage age, taxonomic diversity, and distributional range explain the variations in the cytogenetic traits. Tests were carried out at two taxonomic ranks: within Zingiberaceae and within genus Hedychium using correlations, generalized linear models and phylogenetic least square models. RESULTS: The most frequent changes in chromosome number within Zingiberaceae were noted to be demi-polyploidization and polyploidization (~57% of the time), followed by ascending dysploidy (~27%). The subfamily Zingiberoideae showed descending dysploidy at its base, while Alpinioideae showed polyploidization at its internal nodes. Although chromosome counts and genome sizes did not corroborate with each other, suggesting that they are not equivalent; higher chromosome number variations and higher genome size variations were associated with higher taxonomic diversity and wider biogeographic distribution. CONCLUSIONS: Within Zingiberaceae, multiple incidences of polyploidization were discovered, and cytogenetic events appear to have reduced the genome sizes and increased taxonomic diversity, distributional ranges and invasiveness.


Asunto(s)
Cromosomas de las Plantas , Tamaño del Genoma , Genoma de Planta , Filogenia , Cromosomas de las Plantas/genética , Zingiberaceae/genética , Zingiberaceae/clasificación , Poliploidía , Clima Tropical , Teorema de Bayes , Evolución Molecular , Evolución Biológica
16.
Risk Anal ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38862436

RESUMEN

The enhancing risk from human action and multi-hazard interaction has substantially complicated the hazard-society relationship. The underlying vulnerabilities are crucial in predicting the probable impact to be caused by multi-hazards. Thus, the evaluation of social vulnerability is decisive in inferring the driving factor and preparing for mitigation strategies. The Himalayan landscape is prone to multiple hazards as well as possesses a multitude of vulnerabilities owing to changing human landscape. Thus, an attempt has been made to inquire into the underlying socioeconomic factors enhancing the susceptibility of the region to multi-hazards. The social vulnerability index (SVIent) has been introduced, consisting of 13 indicators and 33 variables. The variables have been standardized using the maximum and minimum normalization method and the relative importance for each indicator has been determined using Shannon entropy methods to compute SVIent. The findings revealed that female population, population above 60 years old, net irrigated area, migrant population, dilapidated house, nonworkers, bank, and nonworkers seeking jobs were found to be relatively significant contributors to the vulnerability. The western part of the study area was classified as the highly vulnerable category (SVI > 0.40628), attributed to high dependence, and higher share of unemployed workers and high poverty. The SVIent was shown to have positive correlation between unemployment, socioeconomic status, migration, dependency, and household structure significant at two-tailed test. The study's impact can be found in influencing the decision of policymakers and stakeholders in framing the mitigation strategies and policy documents.

17.
Environ Monit Assess ; 196(7): 647, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38907768

RESUMEN

In this study, the current distribution probability of Ephedra gerardiana (Somalata), a medicinally potent species of the Himalayas, was assessed, and its spatial distribution change was forecasted until the year 2100 under three Shared Socioeconomic Pathways. Here, we used the maximum entropy model (MaxEnt) on 274 spatially filtered occurrence data points accessed from GBIF and other publications, and 19 bioclimatic variables were used as predictors against the probability assessment. The area under the curve, Continuous Boyce Index, True Skill Statistics, and kappa values were used to evaluate and validate the model. It was observed that the SSP5-8.5, a fossil fuel-fed scenario, saw a maximum habitat decline for E. gerardiana driving its niche towards higher altitudes. Nepal Himalayas witnessed a maximum decline in suitable habitat for the species, whereas it gained area in Bhutan. In India, regions of Himachal Pradesh, Uttarakhand, Jammu and Kashmir, and Sikkim saw a maximum negative response to climate change by the year 2100. Mean annual temperature, isothermality, diurnal temperature range, and precipitation seasonality are the most influential variables isolated by the model that contribute in defining the species' habitat. The results provide evidence of the effects of climate change on the distribution of endemic species in the study area under different scenarios of emissions and anthropogenic coupling. Certainly, the area of consideration encompasses several protected areas, which will become more vulnerable to increased variability of climate, and regulating their boundaries might become a necessary step to conserve the regions' biodiversity in the future.


Asunto(s)
Cambio Climático , Ecosistema , Nepal , India , Bután , Ephedra , Monitoreo del Ambiente , Probabilidad , Factores Socioeconómicos , Modelos Teóricos
18.
Zookeys ; 1200: 65-74, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38751966

RESUMEN

Lycodongammiei (Blanford, 1878), a rarely encountered species of Asian snake, is characterized by ambiguous systematics and biology. Based on a sole specimen of L.gammiei rediscovered in southeastern Xizang, China, we conduct a detailed morphological examination and description, and investigate the systematic position of this species. Morphologically, the newly collected specimen is closely aligned with specimens previously described. Mitochondrial DNA-based phylogenetic analyses reveal that L.gammiei constitutes an independent evolutionary lineage, forming a clade with L.fasciatus (Anderson, 1879), L.gongshan Vogel & Luo, 2011, L.butleri Boulenger, 1900, and L.cavernicolus Grismer, Quah, Anuar, Muin, Wood & Nor, 2014. The closest genetic distance between L.gammiei and its congeners was 10.2%. The discovery of L.gammiei in Medog County, China, signifies an eastward expansion of its known geographical distribution.

19.
Sci Total Environ ; 933: 173187, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38750762

RESUMEN

Cryoconite holes (water and sediment-filled depressions), found on glacier surfaces worldwide, serve as reservoirs of microbes, carbon, trace elements, and nutrients, transferring these components downstream via glacier hydrological networks. Through targeted amplicon sequencing of carbon and nitrogen cycling genes, coupled with functional inference-based methods, we explore the functional diversity of these mini-ecosystems within Antarctica and the Himalayas. These regions showcase distinct environmental gradients and experience varying rates of environmental change influenced by global climatic shifts. Analysis revealed a diverse array of photosynthetic microorganisms, including Stramenopiles, Cyanobacteria, Rhizobiales, Burkholderiales, and photosynthetic purple sulfur Proteobacteria. Functional inference highlighted the high potential for carbohydrate, amino acid, and lipid metabolism in the Himalayan region, where organic carbon concentrations surpassed those in Antarctica by up to 2 orders of magnitude. Nitrogen cycling processes, including fixation, nitrification, and denitrification, are evident, with Antarctic cryoconite exhibiting a pronounced capacity for nitrogen fixation, potentially compensating for the limited nitrate concentrations in this region. Processes associated with the respiration of elemental sulfur and inorganic sulfur compounds such as sulfate, sulfite, thiosulfate, and sulfide suggest the presence of a complete sulfur cycle. The Himalayan region exhibits a higher potential for sulfur cycling, likely due to the abundant sulfate ions and sulfur-bearing minerals in this region. The capability for complete iron cycling through iron oxidation and reduction reactions was also predicted. Methanogenic archaea that produce methane during organic matter decomposition and methanotrophic bacteria that utilize methane as carbon and energy sources co-exist in the cryoconite, suggesting that these niches support the complete cycling of methane. Additionally, the presence of various microfauna suggests the existence of a complex food web. Collectively, these results indicate that cryoconite holes are self-sustaining ecosystems that drive elemental cycles on glaciers and potentially control carbon, nitrogen, sulfur, and iron exports downstream.


Asunto(s)
Cubierta de Hielo , Cubierta de Hielo/química , Regiones Antárticas , Ciclo del Nitrógeno , Ciclo del Carbono , Ecosistema , Carbono/metabolismo , Nitrógeno/análisis
20.
Environ Sci Pollut Res Int ; 31(25): 37196-37214, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38764085

RESUMEN

The transport and deposition of atmospheric pollutants in the Himalayas have a adverse impact on the climate, cryosphere, ecosystem, and monsoon patterns. Unfortunately, there is a insufficiency of data on trace element concentrations and behaviors in the high-altitude Himalayan region, leading to limited research in this area. This study presents a comprehensive and detailed comprehension of trace element deposition, its spatial distribution, seasonal variations, and anthropogenic signals in the high-altitude Kashmir region of the Western Himalayas. Our investigation involved the analysis of 10 trace elements (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in glacier ice, snow pits, surface snow, and rainwater collected at various sites including Kolahoi, Thajwas, Pahalgam (Greater Himalayan ranges), and Kongdori and Shopian (Pir Panjal Ranges) during 2021. The study reveals distinct ranges of concentrations for the trace elements at different sampling sites. Our analysis of trace element concentration depth profiles in snow pits reveals seasonal fluctuations during the deposition year. The highest concentrations were found in the autumn (below 20 cm) and summer (top layer), compared to the winter concentration (10-20 cm). The high enrichment factors (EFs) suggest the severity of human-induced trace metal deposition in the western Himalayan region, relative to surrounding regions. Surprisingly, the concentrations and EFs of trace elements showed seasonal contradictions, with lower concentration values and higher EFs during the non-monsoon season and vice versa. A source apportionment analysis using the positive matrix factorization (PMF) technique identified five sources of trace element deposition in the region, including crustal sources (32.33%), coal combustion (15.62%), biomass burning (17.63%), traffic emission (18.8%), and industrial sources (15.6%). Additionally, the study incorporated backward trajectories coupled with δ18O using the NOAA HYSPLIT model to estimate moisture sources in the region, which suggests atmospheric pollutants predominately deposited from the large-scale atmospheric circulation from westerlies (75%) during non-monsoon season. These findings underscore the urgent need for enhanced monitoring and research efforts in the future.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Estaciones del Año , Oligoelementos , Oligoelementos/análisis , Contaminantes Atmosféricos/análisis , Nieve/química , India , Humanos , Himalayas
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