Assessing the response of Himalayan Alpine Biology to Accelerated Warming

Forest and Ecology Department Forest And Ecology Department March 21, 2024 558 Views

The Forestry and Ecology Department of IIRS established 15 Open Top Chambers (OTC) in September 2022 at Gangotri, Uttarakhand, to delve into the intricate dynamics of Himalayan Alpine Biological Communities under the influence of Experimental Warming. The idea is to test the impact of warming on plant phenology, plant height, biomass and nutrient concentration between OTCs and control plots. Preliminary findings from this endeavour have unveiled compelling insights. With an average annual air temperature increase of 1.28°C and soil temperature rising by 1.06°C, the experiment has effectively augmented the Growing Degree Days (GDD) by a substantial 1612.44°C from March to October within the OTCs, surpassing the 1310.87°C recorded in control plots. It led to early flowering in alpine plants (~10 days); Individuals subjected to elevated temperature had leaf areas 13% to 19% bigger than those present in the ambient environment; 85.46 % to 94.75% increase in shoot length by June and 39.29% increase in peak biomass as compared with natural conditions. Higher average photosynthesis rate was also observed within OTC for most of the species. In the realm of soil dynamics, comparisons of respiration rates between OTCs and control plots reveal a notably higher activity within the former, indicative of heightened biological activity and potentially accelerated nutrient cycling processes. These findings carry profound implications amidst the backdrop of escalating warming trends in the Himalaya. The following illustration depicts the OTC set up along with in-situ measurements.