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In the era of anthropocene, global warming tends to alter the distribution range of the plant species. Highly fragile to such changes are the species that are endemic, inhabit higher elevations and show narrow distribution ranges. Predicting and plotting the appropriate suitable habitats and keeping knowledge of how climate change will affect future distribution become imperative for designing effective conservation strategies. In the current study we have used BIOMOD ensemble forecasting to study the current and predict the future potential distribution of Dactylorhiza hatagirea and Rheum webbianum and describe their niche dynamics in Himalayan biodiversity hotspots under climate change scenarios using ecospat R package. Results reveal sufficient internal evaluation metrics with area under curve (AUC) and true skill statistic (TSS) values greater than 0.8 i.e. 0.93 and 0.98 and 0.82 and 0.90 for D. hatageria and R. webbianum respectively, which signifies robustness of the model. Among different bioclimatic variables, bio_1, bio_3, bio_8, bio_14 and bio_15 were the most influential, showing greater impact on the potential distribution of these plant species. Range change analysis showed that both the studied species will show significant contraction of their suitable habitats under future climatic scenarios. Representative Concentration Pathway (RCP) 8.5 for the year 2070, indicate that the suitable habitats could be reduced by about 51.41% and 70.57% for D. hatagirea and R. webbianum respectively. The results of the niche comparisons between the current and future climatic scenarios showed moderate level of niche overlap for all the pairs with D. hatageria showing 61% overlap for current vs. RCP4.5 2050 and R. webbianum reflects 68% overlap for current vs. RCP4.5 2050. Furthermore, the PCA analysis revealed that climatic conditions for both the species vary significantly between current and future scenarios. The similarity and equivalence test showed that the niche between present and future climate change scenarios is comparable but not identical. From the current study we concluded that the influence of climate change on the habitat distribution of these plant species in the Himalayan biodiversity hotspots can be considered very severe. Drastic reduction in overall habitat suitability poses a high risk of species extinction and thereby threatens to alter the functions and services of these fragile ecosystems. Present results can be used by conservationists for mitigating the biodiversity decline and exploring undocumented populations on one hand and by policymakers in implementing the policy of conservation of species by launching species recovery programmes in future on the other. The outcomes of this study can contribute substantially to understand the consequences of climate change in the Himalayan biodiversity hotspots. [ABSTRACT FROM AUTHOR]

In spite of the high economic value of the Saussurea species in the Indian Himalayan Region (IHR), the potential of most of the species is yet to be investigated. Therefore, an attempt has been made to study the diversity, distribution, habitat preference, nativity, endemism, status and indigenous uses of Saussurea species in the IHR. A total of 62 species were recorded from the IHR; of these, 37 species were native to the Himalayan region, 8 were endemic and 21 were near endemic to the IHR. Twenty-seven of the 28 species that were known to have indigenous uses also had medicinal value and are used for the treatment of various diseases/ailments. Many species, e.g., S. affinis (Ganga Mula*), S. auriculata (Pachak Kut), S. bracteata (Prerak Mul), S. costus (Kuth), S. gossypiphora (Kasturi Kamal) and S. obvallata (Brahm Kamal), have multiple uses. The genus showed high habitat specificity in that 16 species were recorded to be restricted to one or two habitats only. As many as 44 species were identified as rare in the study region. Considering the high industrial demand for raw materials and the endangered status of S. costus, S. gossypiphora, S. obvallata and S. simpsoniana (Fen Kamal), these species should be prioritized for conservation (in situ and ex situ) throughout the IHR. Population assessment of the rare-endangered, native, endemic and economically important species using standard ecological methods has been suggested for the quantification of the existing stock of these species in their natural habitats. Further, phytochemical investigations for the identification of active ingredients are suggested. Propagation and cultivation techniques are lacking for most of the species of Saussurea except for S. costus, S. obvallata and S. medusa (Snow Lotus). Furthermore, the native communities need to be sensitized to the sustainable use and conservation value of the species in this genus. [ABSTRACT FROM AUTHOR]