Integrating environmental variables and biotic interactions to predict the future distribution of the endangered...

Human activities and climate change accelerate habitat loss and fragmentation, threatening medicinal plants and rare species that play important roles in maintaining ecosystem balance. However, the lack of comprehensive and reliable data on their spatial distribution has restricted effective conservation management efforts. This study provides a comprehensive ecological assessment of the endangered high-altitude medicinal plant Aconitum heterophyllum, examining its ecological interactions, environmental drivers, and projected distribution under climate change in Azad Jammu and Kashmir, Pakistan. A total of 129 plant taxa comprising 46 families were recorded from all sampling plots with Asteraceae, Ranunculaceae, and Polygonaceae being dominant. The most common life form was herb (88.37%), hemicryptophytes (57.36%) and microphylls (55.81%), which is an indication of the ecological niche of cold and alpine conditions. Hierarchical clustering and indicator species analysis grouped the sites in three specific plant communities, namely, Abies pindrow-Viburnum grandiflorum-Achillea millefolium (AVA), Swertia petiolataIris-Iris kashmiriana-Potentilla nepalensis (SIP), and Pedicularis pectinate-Juncus himalensis-Parnassia nubicola (PJP). SIP plots located at mid-altitudes (2900-3100 m) showed the highest abundance of A. heterophyllum, whereas AVA (lower altitudes) and PJP (higher altitudes) exhibited moderate to low abundance. Non-metric Multidimensional Scaling (NMDS) and beta-diversity analyses confirmed significant floristic turnover among associations, with the PJP group displaying greater internal heterogeneity. Canonical Correspondence Analysis (CCA) identified altitude as the most influential variable (pseudo-F = 9.0, p = 0.002), strongly shaping the composition of associated plant communities. A generalized linear model (GLM) demonstrated a significant negative relationship between A. heterophyllum abundance and altitude (p = 0.0089), confirming a mid-altitude ecological optimum. Species distribution modeling using MaxEnt (AUC = 0.996) identified summer temperature (bio5) and precipitation (bio18) as the dominant climatic constraints. Currently suitable habitats are narrowly distributed above 2700 m. Future projections suggest limited upslope shifts under SSP-245, whereas SSP-585 indicates substantial altitudinal and latitudinal expansion. However, increased fragmentation and thermal stress may threaten population stability. These findings highlights the species' ecological specialization and vulnerability to climate change, emphasizing the need for integrated conservation strategies combining current ecological baselines, topographic mapping, and forward-looking climatic risk assessment.