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Himalaya, the highest mountain system in the world and house of important biodiversity hotspot, is sensitive to projected warming by climate change. Rhizocarpon geographicum (map lichen), a crustose lichen, grows in high mountain ranges, is a potential indicator species of climate change. In the present study, MaxEnt species distribution modeling algorithm was used to predict the suitable habitat for R. geographicum in current and future climate scenarios. Nineteen bioclimatic variables from WorldClim database, along with elevation, were used to predict the current distribution and three representative concentration pathway (RCP) scenarios by integrating three general circulation models (GCMs) for future distribution of species covering years 2050 and 2070. Furthermore, we performed change analysis to identify the precise difference between the current and future distribution of suitable areas of the species for delineating habitat range expansion (gain), habitat contraction (loss), and stable habitats. The final ensemble model obtained had average test value 0.968, and its predicted ~ 27.5% of the geographical area in the Indian Himalayan Region is presently climatically suitable for the species. The predicted highly suitable area for R. geographicum is observed to be declining in Northwestern Himalaya, and it is shifting towards the higher elevation areas of the Eastern Himalaya. The projected distribution in future under the RCP scenarios (RCP 4.5, 6.0, and 8.5) showed the range expansion towards higher elevations, and it is more pronounced for the extreme future scenarios (RCP 8.5) than for the moderate and intermediate climate scenarios (RCP 4.5 and RCP 6.0). However, assuming that species can migrate to previously unoccupied areas, the model forecasts a habitat loss of 10.86–16.51% for R. geographicum, which is expected due to increase in mean annual temperature by 1.5–3.7 °C. The predictive MaxEnt modeling approach for mapping lichen will contribute significantly to the understanding of the impact of climate change in Himalayan ecosystems with wide implications for drawing suitable conservation plans and to take adaptation and mitigation measures. [ABSTRACT FROM AUTHOR]

Springs and streams are essential sources of fresh water for the Himalayan population. To global and regional extents, these resources are being severely affected by climate change as well as anthropogenic activities. However, the effects of seismicity also have considerable influence on springs but are negligibly studied in that aspect. Crustal deformation, shaking, and movement of the earth's surface due to an earthquake, can modify the stream flow and water level in wells through consolidation of surficial deposits and development of new fractures. The present study addresses the effect of an earthquake on water springs in a seismically active zone. On 18 September 2011, the Sikkim Himalaya experienced a strong earthquake of magnitude (Mw) 6.9. To assess the impact of this earthquake on hydrology, we studied the springs located in the South Sikkim district, India. Our research indicates that few springs dried up following the Mw 6.9 earthquake in 2011 while some springs discharged at a higher rate than before. The springs which were dried up due to climate change were excluded in this study. Furthermore, our study suggests that in tectonically active mountain ranges, like Himalaya, an earthquake not only causes surficial deformations but also influences the hydrological framework at a regional scale. Therefore, the seismic nature of the terrain should also be considered for spring rejuvenation policies. • Impact of an earthquake on water bodies were studied. • Himalayan springs are sensitive to both climate change as well as earthquakes also. • An earthquake having magnitude Mw ≥ 5 may affect the discharge of a spring. [ABSTRACT FROM AUTHOR]