From biodiversity hotspot to conservation hotspot: assessing distribution, population structure, associated flora and habitat geography of threatened Himalayan Yew in temperate forest ecosystems of Kashmir

The Himalayan Yew ( Taxus wallichiana Zucc.) holds a pivotal role in the delicate ecosystems of the moist temperate forests in the Himalayan region, boasting substantial conservation value. The current study was designed to investigate the distribution pattern, community structure, phytosociological attributes, associated flora and conservation of Taxus wallichiana in the temperate forests of the state of Azad Jammu and Kashmir (AJK) Pakistan. Objectives included the creation of GIS-based maps for a detailed representation of Taxus wallichiana distribution in AJK and the identification of its highly fragmented and rapidly dwindling habitats for strategic conservation management. Data was meticulously gathered from 51 temperate forest sites across 6 districts in AJK using quadrate-based systematic sampling. Site selection was based on thorough preliminary surveys of Yew populations in the region. Yew populations at the sampled sites exhibited an average stem density of 371 trees/ha with average basal area cover of 132.12 cm. The species showed extremely low regeneration of 3.35/ha. Floristic inventory revealed a total of 154 plant species belonging to 113 Genera and 50 families as associated flora in the Taxus wallichiana populations. The average values of Simpson's diversity index were recorded as 0.97, Shannon’s Diversity as 3.71, Menhinick’s species richness as 1.21, Pielou’s species evenness as 2.13 whereas community maturity index was 54.26%. Analysis of Life form and Leaf size classes showed that herbaceous Hemicryptophytic microphyllous taxa dominated the local flora. GIS analysis revealed North Facing slopes with moderate degree of steepness and having concave curvature in the moist temperate forest zone as the main habitat of the Taxus wallichiana . Digital Elevation Model (DEM) showed that the species was distributed in an altitudinal range of 1900–2800 m. Significant levels of deforestation recorded as 3.18 Yew stumps/ha synchronized with over grazing and erosion in the study area posing serious threat to the Taxus populations which can lead to local extinction of this species. Through GIS analysis, we precisely mapped both robust and imperiled Taxus populations in AJK, offering vital insights for the conservation management of this species. Cluster Analysis and Pearson’s correlation revealed significant associations among the investigated variables and sampling sites. We urgently recommend immediate conservation measures to safeguard the imperiled Yew populations in the AJK region.