Executive Summary : | In Alpine regions, climate change is a “stress” which is now perceived to have cascading effects from community to species levels. Since last four decades, global mean temperature is increased by 0.835°C and the maximum change occurred high latitudes and in alpine areas (~ 2.0°C)(Shen et al., 2022). This shifting temperature is leading to global decrease in snowfall, reduced snow cover (~13%) and accelerated melting of seasonal snowpack, causing alteration in growing season length of alpine plants (Slatyer et al., 2021). Growing season extension of 10-20 days was already reported (Park et al., 2016) and expected to increase by 40 to 50 days by the end of 21st century (Ruosteenoja et al., 2011). This extension in growing season is evidenced to correspond a period of reduced soil moisture, decreased temperature insulation capacity and nutrients release, exerting strong abiotic stress until later into the growing season. To persist under such stressful environments, plants trigger a sequences of preserved mechanisms to reduce potential damages triggered by those abiotic stresses. In response to these stresses, ecological strategies adapted by plants are mostly reported and investigated in terms of plant functional traits (Magaña Ugarte et al., 2019). Recently, climate change studies (natural and experimental), estimating species response are mainly focused on phenological (Leaf and flower emergence durations), morphological (Leaf area, mass and plant height), reproductive (seed number and mass) and some eco-physiological traits (photosynthesis rate and chlorophyll production), and these studies are limited to certain geographical regions. Similarly, predicting species response to environmental change through climatic models used globally have limitation of not clearly consider species plasticity to acclimatize or adapt to climatic conditions outside those presently occupied niche in the model. So an understanding of the plasticity of species (at niche level) to respond to climate change through experiments is essential to predict future species distributions and population dynamics and to implement successful conservation strategies globally. The temperature and snow melt date are two major climatic factors that were observed to responsible for change in growing season length. These factors are likely to change due to changing climatic factors. This alteration in growing season length is ultimately impacting the productivity, phenology and physiology of vegetation and soil chemistry, which are keys issues of climate change studies in Himalayan region. Principally, due to lack of baseline and long term datasets in Himalaya, IPCC has called it as a ‘white spot’. This it is all the more important in high altitude eco-regions such as the alpine ecosystems. Hence, studies on assessment of impacts of climate change need to be undertaken in the high altitude region, with generation of crucial data on vulnerability of alpine plant species. |