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The physicochemical properties and origins of atmospheric aerosols in the Tibetan Plateau (TP) region are a research topic of great interest, but an in‐depth understanding of this topic is challenging, partially due to a lack of intensive in situ observations. Thus, a field campaign was conducted over Yadong, a remote area on the south slope of the TP from June 11 to 31 August 2021. The aerosol loading was low, with a black carbon mass concentration of 147.4 ± 98.4 ng·m−3. Aerosol single‐scattering albedo was low (0.73 ± 0.11 at 550 nm) and increased from 450 to 700 nm wavelength. Organic matter (OM) accounting for 69.6% of the total aerosol mass and relatively high secondary organic carbon ratios, highlighting the importance of secondary formation. An interesting phenomenon observed was that the evolution of aerosols was mainly characterized by diurnal variation, which could not be explained by large‐scale atmospheric processes such as Indian summer monsoon. Instead, it was found that regional mountain‐valley winds between the Himalayas and South Asia transported polluted air masses toward the TP, especially in the afternoon when regional valley wind are expected to be the strongest and the boundary layer in South Asia is deepest. Additionally, daytime local valley wind further elevated these aerosols to higher altitudes on the TP. This paper provides insights into the transport mechanisms of aerosols from South Asia to the TP. These findings are of great importance since aerosols exhibit significant diurnal variations in the TP region. Plain Language Summary: Previous studies focused on the analysis of the physical or chemical properties of aerosols on the Tibetan Plateau, but this study provides a comprehensive examination of both. The findings reveal that aerosols on the southern slope of the Tibetan Plateau exhibit strong absorption efficiency. Aerosol single‐scattering albedo was low (0.73 ± 0.11 at 550 nm), which may be attributed to aerosol secondary generation and coating. Finally, the mechanism of pollutant transport from South Asia to the Tibetan Plateau was analyzed relies on site observations, satellite, and reanalysis data to highlight the link between diurnal variations of pollutants and transport mechanism. The specific transport mechanism be understood uniformly across different scales, including Indian summer monsoon, regional mountain‐valley winds between the Himalayas and South Asia, and local mountain‐valley winds circulation. Key Points: Aerosol single‐scattering albedo was low (0.73 ± 0.11 at 550 nm) and secondary organic matter was the major aerosol componentThe evolution of aerosols was mainly characterized by diurnal variation that was related to transport mechanism over YadongThe Himalayas‐South Asia regional mountain‐valley winds combined with local mountain‐valley winds transport aerosols to the Tibetan Plateau [ABSTRACT FROM AUTHOR]

Plant lifespan has important evolutionary, physiological, and ecological implications related to population persistence, community stability, and resilience to ongoing environmental change impacts. Although biologists have long been puzzled over the extraordinary variation in plant lifespan and its causes, our understanding of interspecific variability in plant lifespan and the key internal and external factors influencing longevity remains limited. Here, we demonstrate the concurrent impacts of environmental, morphological, physiological, and anatomical constraints on interspecific variation in longevity among > 300 vascular dicot plant species naturally occurring at an elevation gradient (2800–6150 m) in the western Himalayas. First, we show that plant longevity (ranging from 1 to 100 years) is largely related to species' habitat preferences. Ecologically stressful habitats such as alpine and subnival host long‐lived species, while productive ruderal and wetland habitats contain a higher proportion of shorter‐lived species. Second, longevity is influenced by growth form with monocarpic forbs having the shortest lifespan and woody shrubs having the highest. Small‐statured cushion plants with compact canopies and deep roots, most found on cold and infertile alpine and subnival soils, had a higher chance of achieving longevity. Third, plant traits reflecting plant adaptations to stress and disturbance affect interspecific differences in plant longevity. We show that longevity and growth are negatively correlated. Slow‐growing species are those that have a higher chance of reaching a high age. Finally, higher longevity was associated with high leaf carbon and phosphorus, low root phosphorus and nitrogen, and with large bark‐xylem ratio. Our findings suggest that plant longevity in high elevation is intricately determined by a combination of habitat preferences and growth form, as well as the plant growth rate and physiological processes. [ABSTRACT FROM AUTHOR]

The alpine butterfly genus Parnassius is a popular model group for studying biogeography, evolution, conservation biology, and ecology. Despite its scientific importance, a comprehensive and robust phylogeny of this group is still lacking. In this study, we used an amplicon capture strategy to sequence 144 nuclear protein‐coding genes and complete mitochondrial genomes for 60 Parnassius specimens covering 42 species and all eight subgenera of Parnassius. Our results strongly support the monophyly of the genus and eight subgenera. The relationships among subgenera are robustly resolved as (Sachaia, (Kreizbergia, (Driopa, (Parnassius, (Tadumia, Lingamius), (Kailasius, Koramius))))), which is different from all previous results. Biogeographic and divergence time analyses indicate that the ancestor of Parnassius originated in an area including the Himalayas and Tibetan Plateau (HTP) and Mongolian steppes in the middle Miocene approximately 13.19 Mya. The middle Miocene global cooling event (starting from ~13.9 Mya) probably provided climatic opportunities for the diversification of cold‐adapted Parnassius. The ancestral state reconstruction analyses suggest that the ancestor of Parnassius butterflies most likely lived in a medium elevational area (2000–4000 m) and fed on Papaveraceae plants. The host shift from Papaveraceae to Crassulaceae in the subgenus Parnassius increases the species diversity of this subgenus, concurring with the "escape and radiate" hypothesis. Overall, our work provides valuable nuclear gene and mitochondrial genome data and a robust phylogenetic framework of Parnassius for future studies of the taxonomy, evolution, and ecology of this group. [ABSTRACT FROM AUTHOR]

Hydrological processes play an important role in stable isotopic compositional variations of the river water. The present study includes spatial distributions of stable hydrogen and oxygen isotopes (δD and δ18O) of a Himalayan River (the Teesta) to trace various hydrological processes and their associated roles on isotopic fractionation of river water. The δ18O compositions of the water samples varies between −12.2‰ and −5.4‰ (mean: −8.01‰ ± 1.81‰) and that of δD between −95.1‰ and −38.5‰ (mean: −57.6‰ ± 15.6‰). The observed compositional variation in δ18O, δD and d values of river water is mainly governed through snowmelt input, evaporation, and recycled moisture contribution. The variation of δ18O and δD values point towards an early melting of snow in the basin and a significant contribution of snowmelt to the river water. The orographic induced precipitation front appears to control the hydrological regimes in a distinct manner as reflected in the trend between d values and elevation. The rain shadow affected northern reaches of the basin are characterized with dry & arid climate triggering evaporation whereas, the windward southern side witness temperature influenced evaporation. The study suggests that the differential degree of recycled moisture contribution to the local precipitation is also a key component in bringing the stable isotopic variation in the river water. This varied magnitude of moisture recycling could result from uneven distribution of evapotranspiration and surface water evaporation. Results found that a rapid change in the altitude of a river basin can give rise to different hydrometeorological conditions, thereby resulting in simultaneous operation of almost all the major hydrological processes and a complex isotopic compositional variation in the river water. Also, the rainout percentage in the Teesta basin is found to be higher owing to this rapid rate of elevation increase. [ABSTRACT FROM AUTHOR]

Although vegetation has been the focus of recent studies on mountain summits, little is known about smaller‐scale spatial patterns of soil physico‐chemical properties. Here, we report patterns and drivers of soil physico‐chemical properties and their role in shaping the plant diversity on mountain summits of the Himalaya. Using the globally standardized Multi‐Summit Approach, four summits along an elevation gradient from treeline to nival zone were selected in Kashmir Himalaya. Sampling of the summits was carried out to collect soil samples together with vegetation data and soil temperature. The results revealed that there is a significant effect of elevation and aspect on soil physico‐chemical properties and species richness on the summits. A significant correlation was observed between soil parameters and elevation, indicating that summits with distinct pool of species possess distinct soil properties. Moreover, soil temperature clearly determined the aspect‐wise distribution of soil parameters and species richness. The Canonical Correspondence Analysis revealed that elevation, soil temperature, pH, electrical conductivity and C:N ratio were more prominent in determining the plant diversity on summits. Our results demonstrate that mosaic of micro‐climatic conditions driven by elevation and aspect favor a suite of soil properties, which in turn determine the patterns of species diversity on the mountain summits. The present study, therefore, enhances understanding of the spatial patterns of variation in soil and plant diversity of mountain summits, which will help to monitor, model and predict how these ecologically unique ecosystems will respond to climate warming in the Himalaya, with implications for such environments elsewhere. [ABSTRACT FROM AUTHOR]