Spatial Extent of Threatened Medicinal and Aromatic Plants in Alpine Zone of Kumaun, Western Himalaya

The utilization of wild Medicinal and Aromatic Plants (MAPs) has been integral to healthcare practices since the inception of human civilization. The escalating demand for herbal healthcare systems has exerted immense pressure on wild resources, leading to the depletion of several MAP populations. In this context, comprehending the environmental suitability and potential distribution of these species becomes imperative for effective conservation and management. This study seeks to evaluate the potential niche of 25 MAPs in the alpine region of the Kumaun Himalaya through species distribution modelling. The study area encompasses 4617 km2 area between 3000 and 5300 m elevation range. Topographic variables derived from Digital Elevation Models, vegetation types, and climatic variables are considered for assessing habitat suitability. Distribution records of the species are obtained through extensive field surveys conducted in 30 alpine meadows of the Kumaun Himalaya, employing 63 transects and approximately 1120 quadrats following the rapid mapping exercise. Six dominant alpine habitats, including tall forbs, mixed herbaceous, Danthonia grassy slopes, moist alpine scrubs, Kobresia sedge meadows, and marshy meadows, with Danthonia-dominated grassy slopes as the most preferred by MAPs. Analysis of habitat suitability reveals that ~309 km2 area is highly suitable for species reintroduction. Among the MAPs, Picrorhiza kurroa exhibits the maximum potential distribution area (230 km2), while Aconitum balfourii displays the lowest (58 km2) in the region. The MaxEnt model results indicate that altitude, aspect, vegetation type, precipitation during the wettest months, and annual precipitation are the most influential factors determining the potential distribution of MAPs across various habitats.