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Globally, treelines form a transition zone between tree‐dominated forest downslope and treeless alpine vegetation upslope. Treelines represent the highest boundary of "tree" life form in high‐elevation mountains and at high latitudes. Recently, treelines have been shifting upslope in response to climate warming, so it has become important to understand global tree diversity and treeline distributions. However, to the best of our knowledge, no global database on tree flora of treelines exists, which limits our capacity to undertake macroecological analyses. Here, for the first time, we present a global data set on the trees of the treeline ecotone, supported by an online ToTE database. We synthesized the database from 1202 studies published over the last 60 years (1962 to 2022) following the Preferred Reporting Items in Systematic Reviews and Meta‐Analysis (PRISMA) protocol. We classified the tree species in the database into three categories: treeline tree (TL) species, near to treeline (NTL) tree species, and tree species with an upper montane range limit (TUMR). The ToTE Version‐1 presents a total of 208 tree taxa, including 189 species, five subspecies, and 14 varieties, belonging to 54 genera and 26 families distributed across 34 mountain regions worldwide that either grow exactly at the treeline or have a range limit below the treeline. Of the total taxa, 155, 14, and 39 belong to TL, NTL, and TUMR, respectively. Genera such as Abies, Picea, Pinus, Larix, and Juniperus are more represented in the treeline tree category. On the other hand, Acer, Prunus, Populus, and Quercus have more representatives in the near to treeline category, whereas Erica, Nothofagus, and Polylepis contribute more tree species with an upper montane range limit. Furthermore, families such as Rosaceae and Pinaceae include trees that occur both at the treeline and with an upper montane range limit, whereas Sapindaceae includes trees that occur exclusively near to treeline. Our database also includes information on the global distribution patterns of treeline tree species richness across mountains and biomes. The mountains with the highest number of tree species are the Andes (39) followed by the Himalaya (37). Close to 67% of tree species show restricted distributions in different mountains, with the highest endemism in the Andes and the Himalaya. In terms of tree species distribution, Pinus sylvestris was widespread, with a distribution across nine mountain regions, followed by Picea glauca and Fagus sylvatica, both distributed across five mountain regions. In terms of species' distribution across biomes, the temperate biome harbors the highest treeline tree species richness (152 species), which may reflect the fact that the majority of studies are available from the temperate regions of the world. The remaining 56 species are distributed within five other biomes, with the least in dry tropical and subarctic (four species each). Furthermore, currently 40 treeline tree species fall under different International Union for Conservation of Nature threat categories. We anticipate that our database will help advance research on macroecological, biogeographic, evolutionary, climate‐change, and conservation aspects of the treeline on a global scale. The data are released under a Creative Commons Attribution 4.0 international license. Please cite this data paper when the data are reused. [ABSTRACT FROM AUTHOR]

Experimental evidences in support of climate warming–driven phenological shifts are still scarce, particularly from the developing world. Here, we investigated the effect of experimental warming on flowering phenology of selected woody plants in Kashmir Himalaya. We selected the twigs of four congeneric pairs of temperate woody species (Prunus, Populus, Ulmus, Viburnum)—typical spring-flowering plants in the region. Using randomised block design, we monitored these winter dormant twigs in controlled growth chambers to study the effect of different temperature regimes (9, 17, 20 and 23 °C) and species identity on the patterns of phenological shifts. We observed a significant phenological shift in all the species showing preponement in the first flower out and senescence phases ranging from 0.56 to 3.0 and 0.77 to 4.04 days per degree increase in temperature, respectively. The duration of flowering phase in all the species showed a corresponding decrease along the gradient of increasing temperature, which was more driven by preponement of the flower senescence than the start of flowering. The patterns of phenological shifts were highly species-specific, and the magnitude of these shifts significantly varied in all the four pairs of congeneric species despite their phylogenetic similarity. Our study provides experimental support to the previous long-term observation and herbarium-based studies showing that the patterns of phenological shifts in response to global climate warming are likely to vary between species, even those belonging to same evolutionary stock. Our findings highlight that a one-size-fits-all strategy to manage the likely impacts of climate warming–induced phenological shifts will seldom succeed, and should instead be designed for the specific phenological responses of species and regions. [ABSTRACT FROM AUTHOR]

Historically, and even today, discovery of new species has remained one of the primary research activities driving the discipline of taxonomy. Discovering scientifically still unknown biodiversity is critical in addressing the taxonomic impediment which is hampering our progress to meet the challenges of global biodiversity crisis. However, in the rush to accelerate the rate of new species’ discoveries, it is crucial to follow objective, stable and reproducible taxonomic criteria. Otherwise, new species’ discoveries based solely on subjective, unstable and non-reproducible characters can be cause of artificial taxonomic inflation in biodiversity data with wider implications in conservation policy and practice. In this study, by integrating empirical evidences from multiple sources, we critically evaluate the validity of two recently described new species of Ephedra in India (E. sumlingensis and E. khurikensis) to underscore the fact that all ‘new’ species are not always new. Use of morphologically plastic characters in diagnosis, discrepancies in the protologues and inconsistencies with the freshly collected live specimens from the type localities clearly revealed that both these species unambiguously fall within the circumscription of already known E. intermedia. With further support from robust analyses of morphometric and molecular data, we recognise both the species as new synonyms of E. intermedia. Based on the lessons learnt from this study, we suggest recommendations to be practised by the taxonomists to avoid such pitfalls in biodiversity data due to arbitrary new species’ discoveries. [ABSTRACT FROM AUTHOR]

The current paper provides a taxonomic inventory of the vascular plant species collected by the authors during the last two decades from the Rajouri and Poonch districts, located along the Pir Panjal range in the Indian Himalayan State of Jammu and Kashmir. The inventory records a total of 352 species, which belong to 270 genera in 83 families. Of the total taxa, the angiosperms are represented by 331 species in 253 genera and 77 families; gymnosperms by 12 species in 9 genera and 3 families; and pteridophytes by 9 species in 7 genera and 3 families. Asteraceae is the largest family, contributing 42 species; while Artemisia is the largest genus, with 5 species. The inventory is expected to provide baseline scientific data for further studies on plant diversity in these two border districts, and can be used to facilitate the long-term conservation and sustainable use of plant resources in this Himalayan region. [ABSTRACT FROM AUTHOR]

Globally, rapid climate and land-use changes in alpine environments are posing severe risks to their bountiful biodiversity and ecosystem services. Currently, nature-based solutions are fast-emerging as the preferred approach to address the challenges of environmental sustainability. In alpine environments, cushion plants owing to their unique architecture and adaptability offer a potential nature-based system to plan biodiversity conservation and habitat restoration strategies. Here, we employed an analytical framework to test whether and how the cushion plants facilitate the sustenance of alpine plant diversity in Kashmir Himalaya. We specifically aimed to answer: what are the effects of the cushion plants on the patterns of alpine species richness and phylogenetic diversity, and whether these effects vary across spatial scales (local versus landscape), cushion types, and changing elevation. We randomly selected pairs of cushion and neighbouring non-cushion plots (size 100 m2) across 34 different alpine sites in the study region. Within each plot, we randomly laid three 5 m2 quadrats for vegetation sampling, and sampled a total of 204 quadrats in 68 plots with seven cushion types along elevation ranging from 3100 to 3850 m. Our results revealed positive effects of the cushions by supporting a higher community species richness (SR) and phylogenetic diversity (PD). The effects were consistent both at the local (i.e., quadrat) and landscape (i.e., plot) scales, but varied significantly with the cushion type. Interestingly, SR and PD showed an increasing trend with increase in elevation in cushion communities, thereby supporting stress gradient hypothesis. Along the elevational gradient, the cushion communities showed phylogenetic overdispersion, but clustering by non-cushions. Overall, our study provides empirical evidence to reinforce the role of the cushions as conservation refugia for an imperilled alpine plant diversity in the Himalaya. Looking ahead, we highlight the far-reaching implications of our findings in guiding the nature-based environmental management of alpine ecosystems worldwide. [ABSTRACT FROM AUTHOR]

[Display omitted] • Genetic diversity and population structure of endangered Trillium govanianum was investigated. • Based on SSR and SCoT markers, a very low genetic diversity was observed. • A high genetic differentiation and low gene flow was observed among populations. • One polymorphic locus identified for each marker with high discriminatory power. Understanding the genetic diversity and population structure of pharmaceutically important endangered plant species is crucial for their conservation and sustainable use. Despite the continuous population decline in Trillium govanianum Wall. ex D. Don , a highly prized medicinal plant endemic to the Himalaya, information regarding its conservation genetics has been lacking. Here, we employed a conservation genetics approach to investigate how drastically declining populations in natural habitats impact population genetic diversity and structure of this endangered species across the Kashmir Himalaya. We used Start codon targeted (SCoT) and Simple sequence repeat (SSR) markers to assess the intra- and inter-population genetic variation in seven sites across the study region. Based on these markers, we found a very low genetic diversity in T. govanianum populations. Very low levels of observed heterozygosity (Ho = 0.000) and that expected (He = 0.064) in the populations indicate high heterozygote deficiency and high levels of inbreeding depression (F IS = 1.000). A high genetic differentiation was observed among the populations for both SCoT (Gst = 0.719) and SSR (Fst = 0.707) markers. Both the markers showed low gene flow, SCoT (Nm = 0.195) and SSR (Nm = 0.119), depicting high among-population variation than within-population variation. Analysis of molecular variance also indicated a higher genetic variation between the populations than within populations. We also observed a significant positive correlation between genetic divergence and geographical distance, indicating that genetic differentiation in T. govanianum follows a pattern of isolation by distance. Bayesian structure and cluster analysis grouped the populations according to their geographical proximity. Further, redundancy analysis (RDA) revealed the presence of one polymorphic locus for each marker with high discriminatory power. Overall, our findings reveal a very low genetic diversity, high levels of inbreeding, and high genetic differentiation among the populations; likely resulting from habitat fragmentation, population isolation, bottleneck effect, low gene flow, and predominantly asexual reproduction currently operative in the species. Finally, based on the insights gained, we discuss the potential implications of our findings in guiding species recovery and habitat rehabilitation of T. govanianum in the Himalaya with conservation lessons for elsewhere in the world. [ABSTRACT FROM AUTHOR]

• Belowground developmental phenology and its relation with annual aboveground phenology studied in a temperate Himalayan herb Trillium govanianum. • Advanced floral morphogenesis during belowground preformation, including completion of male meiosis and formation of ovules reported in the species. • Belowground floral preformation prior to winter closely linked to aboveground reproductive phenology in ensuing growing season. • Highly advanced belowground preformation minimizes the requirement of prefloration period, thereby ensuring the species' reproductive success. In temperate mountains, the belowground organ preformation prior to winter is a well-known adaptation strategy in perennial plants, however its detailed phenology is still poorly understood, particularly with reference to belowground floral morphogenesis. Here we investigate, in detail, the developmental stages occuring belowground and its relation with annual aboveground phenology in a temperate Himalayan herb Trillium govanianum. We studied the species at three selected sites along an altitudinal gradient in Kashmir Himalaya. At each site, we recorded the aboveground phenological stages and also studied periodically the overwintering belowground buds to characterize the various developmental stages. We measured the size of leaf and floral organs in the belowground preformed bud and also at anthesis aboveground to investigate the differences at these two stages. The results reveal that the leaves and flower in T. govanianum are preformed belowground one season prior to aboveground development. The species shows an advanced stage of floral morphogenesis and development during the belowground preformation, including completion of male meiosis and formation of functional ovules. We found no significant difference in the floral organs like anther and ovary length in the belowground bud and aboveground anthesis stages, thereby clearly indicating that these essential floral organs are fully developed in the preformed bud much before the species enters into winter dormancy. Our study suggests that the highly developed floral preformation hidden from the harsh winter conditions plays a pivotal role in the life history strategy of this temperate herb. Overall, our findings advance the current understanding of the belowground phenology, particularly the process of preformation in temperate herbaceous plants. [ABSTRACT FROM AUTHOR]

• Microclimate modulates edaphic and vegetation patterns at the Himalayan treelines. • High thermal heterogeneity found at downslope and upslope of the treelines. • Growing season mean soil temperatures of 7.31–8.15 °C recorded at the treelines. • Our findings predict treeline potential in several areas beyond the current position. • The study has implications in understanding treeline dynamics under climate change. In an era of global environmental change, the treeline shift triggered by recent climate warming has been reported worldwide. However, it is still unknown how site - specific microclimatic conditions regulate the soil - vegetation relationship at treelines, which constrains our capacity to down-scale broad global trends in the treeline shift at regional scale. In this study, we aimed to unravel fine-scale edaphic and vegetation patterns at two treeline sites in Kashmir Himalaya with in situ - measured microclimate using mini-loggers. At each site, we conducted sampling at the treeline leading edge, 100 and 300 m downslope and upslope. We employed boosted regression trees to find best predictors of the treeline vegetation among the microclimate and edaphic factors. We found intermediate microclimatic conditions at the leading edge but contrasting microclimates at the downslope and upslope. Our results demonstrate that the heterogeneity in microclimate driven by elevation strongly modulates the microsite edaphic conditions at the treelines, which in turn determines the fine-scale vegetation patterns. The soil temperature, moisture, pH, Cu, Zn, electrical conductivity and N were the best predictors of vegetation patterns at the treelines. The length of growing season measured at the treelines matched with the predicted values for the Himalaya, but growing season mean soil temperature of 7.31 – 8.15 °C recorded at the treelines is slightly higher than the postulated 6.4 °C global treeline isotherm. Our findings reveal that the soil microclimate strongly modulates edaphic and vegetation patterns at the treelines, thereby implying that even minor change in microclimate, like ongoing climate warming, can shift the current treeline position. However, this may be partially offset by the higher temperature isotherm in Kashmir Himalaya, thereby suggesting a slow - paced future treeline shift. Overall, the study advances our understanding about the crucial role of microclimate in determining soil-vegetation relationships at treelines with wide implications under ongoing and projected climate change. [Display omitted] [ABSTRACT FROM AUTHOR]

As broad-scale distributions of plants are shaped by climatic conditions, changes of climate necessarily result in shifts of distributional limits. These shifts are closely coupled with changes in plant ecophysiology, growth and productivity. Among environments subjected to the highest increase in temperature in the last decade and the greatest expected warming predicted for the future, high-mountain biomes belong to the most frequently considered. Evidence for distributional shifts has been mostly documented in European and American mountains, while the largest and highest mountainous areas are located in Asia. The present study aims to detect climate change-driven shifts in elevation and ecophysiological traits of endemic herb species of Himalaya with the help of herbarium specimens as potential tool. We observed significant rapid upward elevational shift of 55.2 m/decade compared to average global shifting of 6.1 m/decade and impulsive variations in secondary metabolite concentration. Significant negative relationship was found for stomatal density, δ13C with the lapse of years. Analysis of instrumental temperature data reveals an increase of 0.31°C in mean maximum and 0.79°C in mean minimum temperature during the last century. [ABSTRACT FROM AUTHOR]

In an era of global environmental change, conservation of threatened biodiversity and ecosystem restoration are formidable ecological challenges. The forest understory strata and the belowground soil environment including rhizospheric microbial communities, which are crucial for ecosystem functioning and overall forest biodiversity maintenance, have remained understudied. Here, we investigate the soil microbiome of Trillium govanianum – an endangered Himalayan Forest herb, to unravel the underground diversity, drivers, and potential indicators of the microbial community. We collected rhizospheric and bulk soil samples for microbiome and physicochemical analysis at three sites along an elevation gradient (2500–3300 m) in Kashmir Himalaya. Amplicon sequencing of 16 S rRNA and ITS was used to identify the bacterial and fungal soil microorganisms. We found significant differences in the structure and diversity of microbial community (bacterial and fungal) between the rhizosphere and bulk soil along the altitudinal gradient, and noticeable shifts in the nutrient level in dominant microbial phyla associated with T. govanianum. A significant difference between soil physicochemical parameters and increasing altitude suggests that microbial community structure is determined by altitude and soil type. Similarly, the microbial communities showed a significant (P < 0.05) correlation with soil physicochemical variables along the altitudinal gradient. The moisture content in bacterial and total organic carbon in fungal communities showed the most substantial impact on the physiochemical drivers. We also identify potential bacterial and fungal plant growth promoter indicator species in the soil microbiome of T. govanianum. Overall, our findings provide novel research insights that can be pivotal in designing integrated species recovery programs and long-term restoration plans for T. govanianum, with learnings for biodiversity conservation elsewhere. • Soil microbiome of Trillium govanianum studied to unravel its diversity, drivers and indicator species. • Soil microbial communities showed significant differences in the abundance and diversity. • Physicochemical drivers of soil microbiome differ with increase in altitude. • Significant correlation observed between soil microbial communities and physicochemical drivers. • Bacterial and fungal plant growth promoter indicator species identified. [ABSTRACT FROM AUTHOR]

Dactylorhiza umbrosa (Kar. &Kir.) Nevski is reported for the first time from Kashmir Himalaya, India. A brief description, illustration, photographs of diagnostic features, and a distribution map is provided. Also provided are comparative characters to distinguish D. umbrosa from other species already known from Kashmir Himalaya: D. hatagirea, D. kafiriana and D. viridis. The species shows rare distribution in the alpine habitats of this Himalayan region and overexploitation for local use poses threat to the existence of this rare medicinal orchid species. Therefore, the documentation of this species assumes significance for devising conservation strategies and sustainable use in this Himalayan region. [ABSTRACT FROM AUTHOR]

Despite a wide range of nutritional and nutraceutical diversity existing within the wild germplasm of pomegranate (Punica granatum L.) that can be utilized to develop genetically superior cultivars, little research efforts have been focused on the characterization of this neglected and underutilized crop in the Himalaya. To fill this research gap, the present study carried out in the remote mountainous region of Pir Panjal Himalaya aimed to characterize the morphological variability, assess the genetic variability and relationship among and between the different populations of wild pomegranate, and identify the elite genotype for future plant propagation. We observed significant differences among all the 18 morphological descriptors analyzed; fruit traits showed the highest power of discrimination among the wild pomegranate accessions. Based on ANOVA results, most of the morphological variables showed significant differences among the studied populations (p ˂0.001). Further, redundancy analysis (RDA) revealed that only two fruit traits, the number of arils and aril weight showed a significant relationship within all the populations. Molecular characterization, based on ISSR marker analysis, showed substantial genetic diversity within and between the populations of wild pomegranate in this Himalayan region. In this regard, RDA identified one potentially adaptive locus that strongly affects the different populations of wild pomegranate. Analysis of molecular variance (AMOVA) revealed 58% variation among populations and 42% variation within populations. Our research findings, based on detailed morphological and molecular characterization, provide precious information on the genetic diversity of wild pomegranate. We have identified elite genotypes that can guide climate-smart agriculture based on local genetic resources in this remote Himalayan region. • Germplasm of wild pomegranate in Pir Panjal Himalaya studied. • Fruit traits showed highest power of discrimination. • Number of arils and its weight showed a significant relationship within the populations. • Populations showed significant genetic diversity in the region. • One locus identified that strongly affects different populations of pomegranate. [ABSTRACT FROM AUTHOR]

In an era of climate change, identifying suitable habitats for ecosystem restoration is critical for conservation of globally threatened biodiversity. Here, we integrate the insights gained from ensemble modelling with the community ecology data on threatened Himalayan Trillium (Trillium govanianum) to identify the suitable sites for its habitat restoration. We used ensemble modelling to map the current potential distribution and predict the future suitable habitats for the species under future climate change scenarios. The predictive accuracy of the ensemble model was fairly good; and the most influential variables governing the distribution of Himalayan Trillium were precipitation of the driest month followed by mean diurnal range. The current potential suitable habitats for this species are mostly located in western parts of the Himalaya; however, a range shift from western to eastern Himalaya is predicted under future climate change scenarios. Further, the results of community data revealed that Himalayan Trillium is positively associated with two tree species (Abies pindrow and Taxus wallichiana) forming forest top-story, four understory shrubs (Viburnum grandiflorum, Parrotiopsis jacquemontiana, Skimmia laureola and Rhododendron campanulatum) and one herbaceous species (Podophyllum hexandrum). In particular, the shrubs serve as natural micro-refuges by facilitating the suitable growth and protect the species from unsustainable extraction and livestock grazing. Our findings highlight a two-pronged strategy for habitat restoration of Himalayan Trillium: (i) identification of suitable habitats using ensemble modelling at the pan-Himalayan scale, (ii) and its integration with the community information at local scale. Such an integrated approach offers a nature-based solution in guiding the climate change-integrated restoration programs in the Himalaya, and elsewhere in the world. • Ensemble modelling is integrated with community ecology data on threatened Himalayan Trillium. • Suitable sites for the species' habitat restoration are identified. • Range shift from western to eastern Himalaya is predicted under future climate change. • The associated shrubs provide nature-based solution in the species' habitat restoration. [ABSTRACT FROM AUTHOR]

Understanding the impact of plant invasions on the terrestrial ecosystems, particularly below-ground soil system dynamics can be vital for successful management and restoration of invaded landscapes. Here, we report the impacts of a global plant invader, Leucanthemum vulgare Lam. (ox-eye daisy), on the key physico-chemical soil properties across four sites selected along an altitudinal gradient (1600-2550 m) in Kashmir Himalaya, India. At each site, two types of spatially separated but environmentally similar sampling plots: invaded (IN) and uninvaded (UN) were selected for soil sampling. The results revealed that invasion by L. vulgare had a significant impact on key soil properties in the IN plots. The soil pH, water content, organic carbon and total nitrogen were significantly higher in the IN plots as compared with the UN plots. In contrast, the electrical conductivity, phosphorous and micronutrients, viz. iron, copper, manganese and zinc, were significantly lower in the IN plots as compared with the UN plots. These changes in the soil system dynamics associated with L. vulgare invasion were consistent across all the sites. Also, among the sites, soil properties of low-altitude site (1600 m) were different from the rest of the sampling sites. Overall, the results of the present study indicate that L. vulgare, by altering key properties of the soil system, is likely to influence nutrient cycling processes and facilitates positive feedback for itself. Furthermore, the research insights from this study have wide management implications in the effective ecological restoration of the invaded landscapes.