Plant functional traits of Aconitum Spicatum and Aconitum naviculare along the elevation gradients in central Nepal

Abstract

Plant functional traits strongly influence organisms’ performance and fitness. Traits vary considerably within and among plant species. Elevation gradient provide unique opportunity to examine how plant functional traits vary with changing climate and resources availability. This research aims to assess the responses of functional traits along elevation gradients in two important medicinal plant of Nepal Himalaya Aconitum spicatum (Brühl) Stapf and Aconitum naviculare (Brühl) Stapf, growing in climatically contrasting habitats within Annapurna Conservation Area in central Nepal (moist, southern declivity, and dry, northern declivity of Annapurna mountain range, respectively). Several traits related to leaves (e.g. specific leaf area, leaf nitrogen content), plant growth (e.g. height, basal stem diameter), biomass allocations (e.g. root, stem and leaf mass fraction), and seed production (e.g. output) were measured along the elevation gradient. The relationship between functional traits and elevation were analyzed by generalized linear models. The results revealed that plant height and leaf area declined and root mass fraction increased in both species as elevation increased. However, specific leaf area declined with increasing elevation only in Aconitum naviculare. Leaf nitrogen content did not demonstrate any clear relationship with elevation. Moreover, the root-to-shoot ratio displayed opposite trends in two species, with Aconitum naviculare showing a positive relationship and A. spicatum showing a negative relationship with elevation. The observed patterns in functional traits provide valuable insights into the adaptive strategies of these species in response to changing climate along the elevation gradients. This knowledge can contribute to a better understanding of plant responses to environmental gradients in mountains and aid in their conservation and management efforts under climate change scenarios. Key words: Annapurna Conservation Area, Biomass allocation, Himalaya, Medicinal plants, Specific leaf area