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Elevational gradient, slope, and aspect offer a unique opportunity to explore the response of plant species under changing environmental conditions. The present study aimed to analyze the species diversity and distribution patterns with respect to altitude, aspect, and habitat types in the Kashmir Himalayas. Considering major aspects and habitats, a total of 123 representative sites were selected along the elevational gradients for the present study. The plant species composition of each selected site was studied by organized sampling following the standard ecological methods. During the present study, a total of 361 vascular plant species belonging to 71 families and 214 genera were identified in the study area. At the lower altitudes, the southern aspect and drier habitats showed the highest diversity. Moreover, a significant amount of compositional dissimilarity was observed between the studied aspects, habitats, and elevation belts and was mainly due to species turnover rather than the nestedness component. Further, among the studied variables, altitude was the most important contributing variable, explaining the greatest variation in the species composition. The paired effects of altitude and habitat explained the maximum variation in plant species composition. It may be concluded that floristic diversity should be studied not only with reference to elevational gradients but should also include aspects and habitats. The current study will act as a reference in this direction. A similar study must be replicated in other parts of the Himalayan region in the future to improve our understanding of the distribution and preferences of plant species in mountainous zones. This, in turn, will be immensely helpful in the conservation and sustainable utilization of resources in these ecologically fragile regions.

The Himalayas has a significant impact not just on the Indian subcontinent’s monsoon patterns but also on the global climate. Monsoon failure causing drought has become more common in recent years. As a result, it poses a major threat to ecosystem sustainability. We reported for the first time, a climatic-sensitive tree ring chronology of a broadleaf tree, Rhododendron arboreum, spanning 1732–2017 CE from the Himalayan region. We discovered that the climate during the monsoon season limits the growth of this tree in this region. The correlation analysis between tree ring chronology and climate revealed a significant positive relationship with precipitation (r = 0.63, p < 0.001) and a negative relationship with temperature (r = −0.48, p < 0.01) during the months of June–August (JJA). This strong relationship allowed us to reconstruct monsoon precipitation spanning 1780 to 2017 CE which explained 40% of the variance of the observed climate data for the calibration period. The reconstructed data are validated by the existence of a significant association with the gridded JJA precipitation data of the Climate Research Unit (CRU) of this region. The monsoon rainfall record captured extremely wet years during 1793, 1950, 2011, 2013, and 2017 and extremely dry years during 1812, 1833, 1996, 2002, 2004, and 2005. The extremely dry and wet years well coincided with major catastrophic historical and instrumental droughts and floods in the region. Furthermore, the reconstructed data are also validated by the significant positive correlation (r = 0.36, p < 0.001, n = 163) with the all Indian summer monsoon rainfall series. Such data will be useful to predict the incidence of future droughts, which can help to assess the vulnerability of the forest ecosystem to extreme events.

Analyzing plant species richness across a broad geographic gradient is critical for understanding the patterns and processes of biodiversity. In view of this, a species richness map was developed by stacking the ranges of 51 tree species along an elevational gradient in the Western Himalaya using stacked species distribution models (SSDMs). Among modeling algorithms available in SSDMs, random forest and artificial neural networks exhibited the best performance (r = 0.81, p < 0.001). The predicted tree species richness distribution pattern revealed a mid-elevation peak at around 2,000 m asl, which is in concordance with the observed richness pattern (R2 = 0.94, p < 0.001). Additionally, structural equation models (SEMs) were used to confirm the key factors that influence tree richness. The results based on SEMs confirm that the elevational pattern of predicted tree species richness is explained by mutual effects of water–energy availability, climate, and habitat heterogeneity. This study also validates that the impact of moisture on tree species richness coincides geographically with climate factors. The results have revealed that water–energy-related variables are likely to impact the species richness directly at higher elevations, whereas the effect is more likely to be tied to moisture at lower elevations. SSDMs provide a good tool to predict a species richness pattern and could help in the conservation and management of high biodiverse areas at different spatial scales. However, more investigation is needed to validate the SSDMs in other parts of the Himalayan region to provide a comprehensive synoptic perspective of Himalayan biodiversity at a larger scale.

The recent warming in the mountain regions affect forest productivity in terms of tree growth, especially in the Himalayan region. However, the effects of climate change on the response of radial growth of different age-class trees in the Himalayan region remains unclear. The sensitivity of different age-class trees can differ from younger to old age-class tree growth which create uncertainty in tree-ring calibration against the climatic parameters. In the present study, we assessed the effect of climate change on the radial growth of Cedrus deodara (cedar) from two different age classes; young (age 100 years) in lower temperate zone of Indian Western Himalaya for the period 1950-2015 CE. We modelled basal area increment (BAI) using the Generalized additive model (GAM) which predicted the observed pattern of BAI as a function of year and random effect of tree. The trend of old age stand BAI increased significantly by 0.13 cm2/year whereas it significantly declined by -0.27 cm2/year for young deodar stand. However, from 1990 CE both age classes showed significant decline (p

The present study synthesizes existing literature on Forest Ecosystem Vulnerability (FEV) assessments across the world's mountain regions. The synthesis reveals a globally substantial number of studies are available on FEV assessment. However, such studies are limited in the mountain regions. Of the total 75 peer-reviewed research papers considered for synthesis, there are 61 (81.32%) studies specific to the country, 6 (8%) to continental, 4 (5.34%) to global scales, and the remaining 4 (5.34%) to local. The study results reveal that most assessments are model-based projections, where complex topography of mountains creates uncertainty for climate projections in limited analyses of socio-ecological indicators. Only a few studies (12%) have considered socio-ecological and ground-based data, which are primarily required for adaptation and management planning at the local level. Overall synthesis of literature provided vital information on climate change impacts and suggested management and adaptation plans but was far from a broad reality for the future of the mountain ecosystem under the paradox of climate change. Scales, targets, indicators, and assessment approaches varied widely and focused on only a subset of resources. We recommend forest managers should critically examine the scale, indicators, methods, and targets when planning forest vulnerability assessments. This synthesis of FEV assessment will help suggest the best approaches and indicators given the limited number of model studies in the mountain area for decision and policy making for forest resource management.